Sample records for estuary engineering feasibility

  1. New Bedford Harbor Superfund Project, Acushnet River Estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 3. Characterization and elutriate testing of Acushnet River Estuary sediment. Technical report, August 1985-March 1988

    SciTech Connect

    Averett, D.E.

    1989-03-01

    Several of the alternatives being considered for the New Bedford Harbor Superfund Project involve dredging of contaminated sediment from the Acushnet River Estuary and placement of the contaminated dredged material in confined disposal areas. Evaluation of these alternatives requires testing sediment from the site to determine chemical and physical characteristics, settling properties, contaminant releases for various migration pathways, and treatment requirements for disposal area effluent. The purpose of this report is to describe the estuary composite sediment sample and the hot-spot-sediment sample tested at the US Army Engineer Waterways Experiment Station as part of the US Army Corps of Engineers' Acushnet River Estuary Engineering Feasibility Study of Dredging and Dredged Material Disposal Alternatives. Bulk sediment chemistry, physical characteristics, and elutriate testing for the sediments are included.

  2. New Bedford Harbor Superfund Project, Acushnet River estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 11. Evaluation of conceptual dredging and disposal alternatives. Technical report, August 1985-July 1988

    SciTech Connect

    Averett, D.E.; Palermo, M.R.; Otis, M.J.; Rubinoff, P.B.

    1989-07-01

    This report evaluates conceptual dredging and disposal alternatives for the Acushnet River Estuary, a part of the New Bedford Harbor Superfund Site. Dredging for removal of the highly contaminated sediment and subsequent disposal in upland or nearshore confined disposal facilities or disposal in contaminated aquatic disposal facilities are alternative considered in the Engineering Feasibility Study of Dredging and Dredged Material Disposal Alternatives. Sediment testing and sediment-transport modeling performed as earlier tasks of the study form the basis for evaluation of the alternatives. The technical feasibility of conceptual design options is based on site availability, capacity, and characteristics and on sediment physical characteristics and dredged-material settling behavior as defined by laboratory testing. Contamination releases during dredging and disposal operations are estimated for each disposal option. A preliminary cost estimate for implementation of each option evaluated is alo presented.

  3. New Bedford Harbor Superfund Project: Acushnet River Estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 2. Sediment and contaminant hydraulic transport investigations. Technical report, February 1986-July 1987

    SciTech Connect

    Teeter, A.M.

    1988-12-01

    This report documents the evaluation of hydraulic conditions and sediment migration associated with the dredging and dredged material disposal alternatives proposed for the upper Acushnet River Estuary upstream of New Bedford Harbor, Massachusetts. Dredging and onsite disposal is one remedial measure being considered by the US Environmental Protection Agency. Assessments of sediment and contaminant migration beyond the upper New Bedford Harbor from proposed dredging and disposal alternatives were made based on field, laboratory, and various model studies. The upper estuary was found to be depositional and a reasonably efficient sediment trap. Total suspended material (TSM) concentrations were very low in the system.

  4. Estuaries

    NSDL National Science Digital Library

    2013-12-18

    An estuary is a body of water that is created when freshwater from rivers and streams flows into the saltwater of an ocean. To understand this mixing of fresh and salt water, learners go through several activities: 1) in Salt and Water, learners dissolve salt crystals in water to observe their effects on water; 2) in Making a Salt Wedge, learners make a model of a salt wedge estuary, which occurs in nature when the mouth of a river flows directly into seawater; 3) in Plant Dehydration learners observe the effects of salinity (salt content in the water) on live plants. Includes a wrap-up guide for group discussions.

  5. Artemis: Results of the engineering feasibility study

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Information is given in viewgraph form for the Engineering Feasibility Study of the Artemis Project, a plan to establish a permanent base on the Moon. Topics covered include the Common Lunar Lander (CLL), lunar lander engineering study results, lunar lander trajectory analysis, lunar lander conceptual design and mass properties, the lunar lander communication subsystem design, and product assurance.

  6. New Bedford Harbor Superfund Project Acushnet River estuary engineering feasibility study of dredging and dredged-material disposal alternatives. Report 10. Evaluation of dredging and dredging control technologies. Technical report, August 1985-March 1988

    SciTech Connect

    Palermo, M.R.; Pankow, V.R.

    1988-11-01

    This report presents the results of an evaluation of dredging equipment and techniques for removal of highly contaminated sediments from the upper estuary of the Acushnet River, a portion of the New Bedford Harbor Superfund Project. Site conditions as related to dredge selection and operation, factors considered in selection of equipment, various dredge types considered for use, and operational procedures and controls for sediment resuspension during dredging are described. Each of the dredge types is ranked according to the following criteria: compatibility for full-scale cleanup, availability, safety, potential for sediment resuspension, maneuverability, cleanup precision, cost and production flexibility, required water depth for operation, ability to access the site, and compatibility with disposal options.

  7. Restoration of Hydrodynamic and Hydrologic Processes in the Chinook River Estuary, Washington – Feasibility Assessment

    SciTech Connect

    Khangaonkar, Tarang P.; Breithaupt, Stephen A.; Kristanovich, Felix C.

    2006-01-01

    A hydrodynamic and hydrologic modeling analysis was conducted to evaluate the feasibility of restoring natural estuarine functions and tidal marine wetlands habitat in the Chinook River estuary, located near the mouth of the Columbia River in Washington. The reduction in salmonid populations is attributable primarily to the construction of a Highway 101 overpass across the mouth of the Chinook River in the early 1920s with a tide gate under the overpass. This construction, which was designed to eliminate tidal action in the estuary, has impeded the upstream passage of salmonids. The goal of the Chinook River Restoration Project is to restore tidal functions through the estuary, by removing the tide gate at the mouth of the river, filling drainage ditches, restoring tidal swales, and reforesting riparian areas. The hydrologic model (HEC-HMS) was used to compute Chinook River and tributary inflows for use as input to the hydrodynamic model at the project area boundary. The hydrodynamic model (RMA-10) was used to generate information on water levels, velocities, salinity, and inundation during both normal tides and 100-year storm conditions under existing conditions and under the restoration alternatives. The RMA-10 model was extended well upstream of the normal tidal flats into the watershed domain to correctly simulate flooding anddrainage with tidal effects included, using the wetting and drying schemes. The major conclusion of the hydrologic and hydrodynamic modeling study was that restoration of the tidal functions in the Chinook River estuary would be feasible through opening or removal of the tide gate. Implementation of the preferred alternative (removal of the tide gate, restoration of the channel under Hwy 101 to a 200-foot width, and construction of an internal levee inside the project area) would provide the required restorations benefits (inundation, habitat, velocities, and salinity penetration, etc.) and meet flood protection requirements. The alternative design included design of storage such that relatively little difference in the drainage or inundation upstream of Chinook River Valley Road would occur as a result of the proposed restoration activities.

  8. Restoration of Hydrodynamic and Hydrologic Processes in the Chinook River Estuary, Washington – Feasibility Assessment

    SciTech Connect

    Khangaonkar, Tarang P.; Breithaupt, Stephen A.; Kristanovich, Felix C.

    2006-08-03

    A hydrodynamic and hydrologic modeling analysis was conducted to evaluate the feasibility of restoring natural estuarine functions and tidal marine wetlands habitat in the Chinook River estuary, located near the mouth of the Columbia River in Washington. The reduction in salmonid populations is attributable primarily to the construction of a Highway 101 overpass across the mouth of the Chinook River in the early 1920s with a tide gate under the overpass. This construction, which was designed to eliminate tidal action in the estuary, has impeded the upstream passage of salmonids. The goal of the Chinook River Restoration Project is to restore tidal functions through the estuary, by removing the tide gate at the mouth of the river, filling drainage ditches, restoring tidal swales, and reforesting riparian areas. The hydrologic model (HEC-HMS) was used to compute Chinook River and tributary inflows for use as input to the hydrodynamic model at the project area boundary. The hydrodynamic model (RMA-10) was used to generate information on water levels, velocities, salinity, and inundation during both normal tides and 100-year storm conditions under existing conditions and under the restoration alternatives. The RMA-10 model was extended well upstream of the normal tidal flats into the watershed domain to correctly simulate flooding and drainage with tidal effects included, using the wetting and drying schemes. The major conclusion of the hydrologic and hydrodynamic modeling study was that restoration of the tidal functions in the Chinook River estuary would be feasible through opening or removal of the tide gate. Implementation of the preferred alternative (removal of the tide gate, restoration of the channel under Hwy 101 to a 200-foot width, and construction of an internal levee inside the project area) would provide the required restorations benefits (inundation, habitat, velocities, and salinity penetration, etc.) and meet flood protection requirements. The alternative design included design of storage such that relatively little difference in the drainage or inundation upstream of Chinook River Valley Road would occur as a result of the proposed restoration activities.

  9. Feasibility study for convertible engine torque converter

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The feasibility study has shown that a dump/fill type torque converter has excellent potential for the convertible fan/shaft engine. The torque converter space requirement permits internal housing within the normal flow path of a turbofan engine at acceptable engine weight. The unit permits operating the engine in the turboshaft mode by decoupling the fan. To convert to turbofan mode, the torque converter overdrive capability bring the fan speed up to the power turbine speed to permit engagement of a mechanical lockup device when the shaft speed are synchronized. The conversion to turbofan mode can be made without drop of power turbine speed in less than 10 sec. Total thrust delivered to the aircraft by the proprotor, fan, and engine during tansient can be controlled to prevent loss of air speed or altitude. Heat rejection to the oil is low, and additional oil cooling capacity is not required. The turbofan engine aerodynamic design is basically uncompromised by convertibility and allows proper fan design for quiet and efficient cruise operation. Although the results of the feasibility study are exceedingly encouraging, it must be noted that they are based on extrapolation of limited existing data on torque converters. A component test program with three trial torque converter designs and concurrent computer modeling for fluid flow, stress, and dynamics, updated with test results from each unit, is recommended.

  10. Measuring the contribution of benthic ecosystem engineering species to the ecosystem services of an estuary: A case study of burrowing shrimps in Yaquina Estuary, Oregon - April 2009

    EPA Science Inventory

    Burrowing shrimps are regarded as ecosystem engineering species in many coastal ecosystems worldwide, including numerous estuaries of the west coast of North America (Baja California to British Columbia). In estuaries of the U.S. Pacific Northwest, two species of large burrowing...

  11. Measuring the contribution of benthic ecosystem engineering species to the ecosystem services of an estuary: A case study of burrowing shrimps in Yaquina Estuary, Oregon

    EPA Science Inventory

    Burrowing shrimps are regarded as ecosystem engineering species in many coastal ecosystems worldwide, including numerous estuaries of the west coast of North America (Baja California to British Columbia). In estuaries of the U.S. Pacific Northwest, two species of large burrowing...

  12. Stirling engine design and feasibility for automotive use

    Microsoft Academic Search

    Collie

    1979-01-01

    The book is based on two reports dealing with theoretical considerations in the design of Stirling engines for automotive use, and with a feasibility study for an 80-100-hp automotive Stirling engine. The basic principles of heat engines are explained, and the Stirling engine is introduced, with attention given to the variety of Stirling engine types and their utility in comparison

  13. Engineering aspects of site-specific oil spill contingency planning for estuaries

    E-print Network

    James, David Woody

    1984-01-01

    ENGINEERING ASPECTS OF SITE-SPECIFIC OIL SPILL CONTINGENCY PLANNING FOR ESTUARIES A Thesis by DAVID WOODY JAMES Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1984 Major Subject: Civil Engineering ENGINEERING ASPECTS OP SITE-SPECIFIC OIL SPILL CONTINGENCY PLANNING FOR ESTDARIES A Thesis by DAVID WOODY JAMES Approved as to style and content by: Dr. Ro W. Bann, Jr. (Chairman of Committee) Dr...

  14. Laser engines operating by resonance absorption. [thermodynamic feasibility study

    NASA Technical Reports Server (NTRS)

    Garbuny, M.; Pechersky, M. J.

    1976-01-01

    Basic tutorial article on the thermodynamic feasibility of laser engines at the present state of the art. Three main options are considered: (1) laser power applied externally to a heat reservoir (boiler approach); (2) internal heating of working fluid by resonance absorption; and (3) direct conversion of selective excitation into work. Only (2) is considered practically feasible at present. Basic concepts and variants, efficiency relations, upper temperature limits of laser engines, selection of absorbing gases, engine walls, bleaching, thermodynamic cycles of optimized laser engines, laser-powered turbines, laser heat pumps are discussed. Photon engines and laser dissociation engines are also considered.

  15. 75 FR 77798 - Interpretation of OSHA's Provisions for Feasible Administrative or Engineering Controls of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-14

    ...Provisions for Feasible Administrative or Engineering Controls of Occupational Noise AGENCY...Provisions for Feasible Administrative or Engineering Controls of Occupational Noise, giving...Provisions for Feasible Administrative or Engineering Controls of Occupational Noise....

  16. Magma energy: engineering feasibility of energy extraction from magma bodies

    SciTech Connect

    Traeger, R.K.

    1983-12-01

    A research program was carried out from 1975 to 1982 to evaluate the scientific feasibility of extracting energy from magma, i.e., to determine if there were any fundamental scientific roadblocks to tapping molten magma bodies at depth. The next stage of the program is to evaluate the engineering feasibility of extracting energy from magma bodies and to provide insight into system economics. This report summarizes the plans, schedules and estimated costs for the engineering feasibility study. Tentative tasks and schedules are presented for discussion and critique. A bibliography of past publications on magma energy is appended for further reference. 69 references.

  17. ILLINOIS -RAILROAD ENGINEERING A Feasibility Study of MachineA Feasibility Study of Machine--Vision InspectionVision Inspection

    E-print Network

    Barkan, Christopher P.L.

    ILLINOIS - RAILROAD ENGINEERING A Feasibility Study of MachineA Feasibility Study of Machine Railroad Engineering Seminar SeriesWilliam W. Hay Railroad Engineering Seminar Series 30 January 200930 January 2009 Bryan Schlake, Riley Edwards, and Chris Barkan Railroad Engineering Program Narendra Ahuja

  18. Civil Engineering Feasibility Studies for Future Ring Colliders at CERN

    E-print Network

    Bruning, O; Myers, S; Osborne, J; Rossi, L; Waaijer, C; Zimmermann, F

    2013-01-01

    CERN civil engineers are studying the feasibility of several potential ring colliders to complement the LHC: an 80km circular tunnel to house the TLEP and VHE-LHC, and the ring-ring and linac-ring options for the LHeC. The feasibility of these projects is largely dependent on civil design and geotechnical and environmental risks. As civil infrastructure works typically represent one third of the cost of major physics projects, it is critical that the construction costs are well understood from the conceptual stage. This proceeding presents the first results of the feasibility studies for the 80km tunnel and the linac-ring LHeC. Presented at IPAC'13 Shanghai, 12-17 May 2013

  19. Disturbance facilitates the coexistence of antagonistic ecosystem engineers in California estuaries.

    PubMed

    Castorani, Max C N; Hovel, Kevin A; Williams, Susan L; Baskett, Marissa L

    2014-08-01

    Ecological theory predicts that interactions between antagonistic ecosystem engineers can lead to local competitive exclusion, but disturbance can facilitate broader coexistence. However, few empirical studies have tested the potential for disturbance to mediate competition between engineers. We examined the capacity for disturbance and habitat modification to explain the disjunct distributions of two benthic ecosystem engineers, eelgrass Zostera marina and the burrowing ghost shrimp Neotrypaea californiensis, in two California estuaries. Sediment sampling in eelgrass and ghost shrimp patches revealed that ghost shrimp change benthic biogeochemistry over small scales (centimeters) but not patch scales (meters to tens of meters), suggesting a limited capacity for sediment modification to explain species distributions. To determine the relative competitive abilities of engineers, we conducted reciprocal transplantations of ghost shrimp and eelgrass. Local ghost shrimp densities declined rapidly following the addition of eelgrass, and transplanted eelgrass expanded laterally into the surrounding ghost shrimp-dominated areas. When transplanted into eelgrass patches, ghost shrimp failed to persist. Ghost shrimp were also displaced from plots with structural mimics of eelgrass rhizomes and roots, suggesting that autogenic habitat modification by eelgrass is an important mechanism determining ghost shrimp distributions. However, ghost shrimp were able to rapidly colonize experimental disturbances to eelgrass patch edges, which are common in shallow estuaries. We conclude that coexistence in this system is maintained by spatiotemporally asynchronous disturbances and a competition-colonization trade-off: eelgrass is a competitively superior ecosystem engineer, but benthic disturbances permit the coexistence of ghost shrimp at the landscape scale by modulating the availability of space. PMID:25230478

  20. MORE THAN JUST BAIT: BURROWING SHRIMP AS ECOSYSTEM ENGINEERS IN OREGON ESTUARIES - SEPTEMBER 2006

    EPA Science Inventory

    Burrowing shrimp may be most widely known as excellent fishing bait, but they also play important roles in estuaries of the Pacific Northwest. These shrimps strongly affect carbon and nutrient cycling, phytoplankton abundance, food web structure and dynamics, sediment stability,...

  1. Engineering assessment and feasibility study of Chattanooga Shale as a future source of uranium

    SciTech Connect

    Not Available

    1978-06-01

    This report describes the engineering, feasibility, economics, and environmental aspects of exploitation of Chattanooga Shale to recover U, synthetic crude oil, and byproduct Th, NH/sub 3/, S, Mo, V, Ni, and Co. It is concluded that the shale is a potential source of U, energy, and byproduct metals. This volume of the report covers the engineering description, feasibility, and economics of exploitation of the shale. (DLC)

  2. Will the balance of power shift among native eastern Pacific estuary ecosystem engineers with the introduced bopyrid isopod parasite orthione griffenis?

    EPA Science Inventory

    The blue mud shrimp, Upogebia pugettensis, the bay ghost shrimp, Neotrypaea californiensis, and eelgrass, Zostera marina are endemic ecosystem engineers that define the ecological structure and function of estuaries along the Pacific coast of the US as significantly as do marshes...

  3. Session 6: Magma Energy: Engineering Feasibility of Energy Extraction from Magma Bodies

    SciTech Connect

    Traeger, R.K.

    1983-12-01

    Extensive quantities of high-quality energy are estimated to be available from molten magma bodies existing within 10 Km of the US continent's surface. A five-year study sponsored by DOE/BES demonstrated that extraction of energy from these melts was scientifically feasible. The next stage of assessment is to evaluate the engineering feasibility of energy extraction and provide a preliminary economic evaluation. Should the second step demonstrate engineering feasibility, the third step would include detailed economic, market and commercialization endeavors. Evaluation of the engineering feasibility will be initiated in FY 84 in a program supported by DOE/GHTD and managed by Dave Allen. The project will be managed by Sandia Labs in James Kelsey's Geothermal Technology Development Division. The project will continue to draw on expertise throughout the country, especially the scientific base established in the previous BES Magma Energy Program.

  4. Estuary Live!

    NSDL National Science Digital Library

    Classrooms and individuals can log on to participate in a real-time field trip to a National Estuary Research Reserve. Ask questions, view live video and still images, and learn about estuaries from experts. Topics range from geology to water quality, estuary plants and animals, and cultural heritage. Includes: references and lesson plans, classroom activities and teachers' guides. Archives of previous years are available, featuring sessions from East, West and Gulf Coast estuaries.

  5. Exoskeletal Engine Concept: Feasibility Studies for Medium and Small Thrust Engines

    NASA Technical Reports Server (NTRS)

    Halliwell, Ian

    2001-01-01

    The exoskeletal engine concept is one in which the shafts and disks are eliminated and are replaced by rotating casings that support the blades in spanwise compression. Omission of the shafts and disks leads to an open channel at the engine centerline. This has immense potential for reduced jet noise and for the accomodation of an alternative form of thruster for use in a combined cycle. The use of ceramic composite materials has the potential for significantly reduced weight as well as higher working temperatures without cooling air. The exoskeletal configuration is also a natural stepping-stone to complete counter-rotating turbomachinery. Ultimately this will lead to reductions in weight, length, parts count and improved efficiency. The feasibility studies are in three parts. Part I-Systems and Component Requirements addressed the mechanical aspects of components from a functionality perspective. This effort laid the groundwork for preliminary design studies. Although important, it is not felt to be particularly original, and has therefore not been included in the current overview. Part 2-Preliminary Design Studies turned to some of the cycle and performance issues inherent in an exoskeletal configuration and some initial attempts at preliminary design of turbomachinery were described. Twin-spoon and single-spool 25.800-lbf-thrust turbofans were used as reference vehicles in a mid-size commercial subsonic category in addition to a single-spool 5,000-lbf-thrust turbofan that represented a general aviation application. The exoskeletal engine, with its open centerline, has tremendous potential for noise suppression and some preliminary analysis was done which began to quantify the benefits. Part 3-Additional Preliminary Design Studies revisited the design of single-spool 25,800-lbf-thrust turbofan configurations, but in addition to the original FPR = 1.6 and BPR = 5.1 reference engine, two additional configurations used FPR = 2.4 and BPR = 3.0 and FPR = 3.2 and BPR = 2.0 were investigated. The single-spool 5,000-lbf-thrust turbofan was refined and the small engine study was extended to include a 2,000-lbf-thrust turbojet. More attention was paid to optimizing the turbomachinery. Turbine cooling flows were eliminated, in keeping with the use of uncooled CMC material in exoskeletal engines. The turbine performance parameters moved much closer to the nominal target values, demonstrating the great benefits to the cycle of uncooled turbines.

  6. Exoskeletal Engine Concept: Feasibility Studies for Medium and Small Thrust Engines

    NASA Technical Reports Server (NTRS)

    Halliwell, Ian

    2001-01-01

    The exoskeletal engine concept is one in which the shafts and disks are eliminated and are replaced by rotating casings that support the blades in spanwise compression. Omission of the shafts and disks leads to an open channel at the engine centerline. This has immense potential for reduced jet noise and for the accommodation of an alternative form of thruster for use in a combined cycle. The use of ceramic composite materials has the potential for significantly reduced weight as well as higher working temperatures without cooling air. The exoskeletal configuration is also a natural stepping-stone to complete counter-rotating turbomachinery. Ultimately this will lead to reductions in weight, length, parts count and improved efficiency. The feasibility studies are in three parts. Part 1: Systems and Component Requirements addressed the mechanical aspects of components from a functionality perspective. This effort laid the groundwork for preliminary design studies. Although important, it is not felt to be particularly original, and has therefore not been included in the current overview. Part 2: Preliminary Design Studies turned to some of the cycle and performance issues inherent in an exoskeletal configuration and some initial attempts at preliminary design of turbomachinery were described. Twin-spoon and single-spool 25,800-lbf-thrust turbofans were used as reference vehicles in a mid-size commercial subsonic category in addition to a single-spool 5,000-lbf-thrust turbofan that represented a general aviation application. The exoskeletal engine, with its open centerline, has tremendous potential for noise suppression and some preliminary analysis was done which began to quantify the benefits. Part 3: Additional Preliminary Design Studies revisited the design of single-spool 25,800-lbf-thrust turbofan configurations, but in addition to the original FPR = 1.6 and BPR = 5.1 reference engine. two additional configurations used FPR = 2.4 and BPR = 3.0 and FPR = 3.2 and BPR = 2.0 were investigated. The single-spool 5.000-lbf-thrust turbofan was refined and the small engine study was extended to include a 2,000-lbf-thrust turbojet. More attention was paid to optimizing the turbomachinery. Turbine cooling flows were eliminated, in keeping with the use of uncooled CMC materials in exoskeletal engines. The turbine performance parameters moved much closer to the nominal target values, demonstrating the great benefits to the cycle of uncooled turbines.

  7. Reverse Engineering Time Discrete Finite Dynamical Systems: A Feasible Undertaking?

    PubMed Central

    Delgado-Eckert, Edgar

    2009-01-01

    With the advent of high-throughput profiling methods, interest in reverse engineering the structure and dynamics of biochemical networks is high. Recently an algorithm for reverse engineering of biochemical networks was developed by Laubenbacher and Stigler. It is a top-down approach using time discrete dynamical systems. One of its key steps includes the choice of a term order, a technicality imposed by the use of Gröbner-bases calculations. The aim of this paper is to identify minimal requirements on data sets to be used with this algorithm and to characterize optimal data sets. We found minimal requirements on a data set based on how many terms the functions to be reverse engineered display. Furthermore, we identified optimal data sets, which we characterized using a geometric property called “general position”. Moreover, we developed a constructive method to generate optimal data sets, provided a codimensional condition is fulfilled. In addition, we present a generalization of their algorithm that does not depend on the choice of a term order. For this method we derived a formula for the probability of finding the correct model, provided the data set used is optimal. We analyzed the asymptotic behavior of the probability formula for a growing number of variables n (i.e. interacting chemicals). Unfortunately, this formula converges to zero as fast as , where and . Therefore, even if an optimal data set is used and the restrictions in using term orders are overcome, the reverse engineering problem remains unfeasible, unless prodigious amounts of data are available. Such large data sets are experimentally impossible to generate with today's technologies. PMID:19295916

  8. Exploring Estuaries

    NSDL National Science Digital Library

    Defines estuaries and related habitats, reviews their roles in coastal ecology and in supporting human activities. Virtual tours provide history and introduce ecology of representative plans and animals. Presents current threats to estuaries and their wildlife and explains the role of EPA's National Estuary Program in protecting these important coastal resources. Includes: teachers' page with resources and links; games, coloring sheets and glossary for kids.

  9. Krypton-85 hydrofracture engineering feasibility and safety evaluation

    SciTech Connect

    Peretz, F.J.; Muller, M.E.; Pan, P.Y.

    1981-07-01

    Engineering studies have been made to determine the hazards associated with the disposal of /sup 85/Kr using the hydrofracture process. To assess the hazards, an effort has been made to identify the equipment required to entrain and dissolve the noble gas into the grout stream at hydrofracture pressure (up to 350 bar). Off-the-shelf or slightly modified equipment has been identified for safe and effective compression and gas-grout mixing. Each monthly injection disposes of 1.6 x 10/sup 6/ Ci of /sup 85/Kr. By connecting only one gas cylinder to the injection system at a time, the maximum amount of krypton likely to be released as a result of equipment failure is limited to 128,000 Ci. An evaluation by Los Alamos Technical Associates shows that releasing this amount of gas in less than one hour under worst-case meteorological conditions through a 30-m stack would result in a whole-body dose of 170 millirem at a distance of 1 km from the facility. A krypton collection and recovery system can further reduce this dose to 17 millirem; increasing the distance to the site boundary to 3 km can also reduce the dose by a factor of ten. Lung and skin dose estimates are 1.6 and 120 times the whole-body dose, respectively. These are all worst-case values; releases under more typical conditions would result in a significantly lower dose. No insurmountable safety or engineering problems have been identified.

  10. Energy efficiency and economic feasibility of CCHP driven by stirling engine

    Microsoft Academic Search

    X. Q. Kong; R. Z. Wang; X. H. Huang

    2004-01-01

    This paper deals with the problem of energy efficiency evaluation and economic feasibility analysis of a small scale trigeneration system for combined cooling, heating and power generation (CCHP) with an available Stirling engine. Trigeneration systems have a large potential of energy saving and economical efficiency. The decisive values for energetic efficiency evaluation of such systems are the primary energy rate

  11. GEO-ENGINEERING TO CONFINE CLIMATE CHANGE: IS IT AT ALL FEASIBLE?

    E-print Network

    Begstsson, Lennart

    on climate change where the warming from increasing greenhouse gases and the cooling from sulfate aerosolsGEO-ENGINEERING TO CONFINE CLIMATE CHANGE: IS IT AT ALL FEASIBLE? An Editorial Comment 1 carbon dioxide concentration irrespective of the warming of the climate. 2. How Predictable is Climate

  12. A feasibility study of a new ATREX engine system of aft-turbine configuration

    NASA Astrophysics Data System (ADS)

    Isomura, Kousuke; Omi, Junsuke; Tanatsugu, Nobuhiro; Sato, Tetsuya; Kobayashi, Hiroaki

    2002-07-01

    A feasibility of ATREX (Air-Turbo-Ram Expander cycle) engine with conventional aft-turbine configuration has been studied to be developed in about 10 years, if the development project has started under enough resources. The novel tip-turbine of the original ATREX engine is replaced by a conventional aft-turbine, and the maximum turbine inlet temperature (TTT) is reduced to 1200K, to realize the engine by only using approved metal technologies of modern jet engines. The capability of the performance has been shown by parametric studies by changing components' design parameters. The study shows that the performance of the ATREX engine is not less than that of pre-cooled turbo jet. Some technical issues on developing the new ATREX engine have been addressed. The most important issue would come from the transient total temperature change due to the rapid acceleration from sea level static (SLS) condition (288K) to Mach 6 at 30km of altitude (1680K) in 6 minutes. The deformation due to transient thermal expansion has to be controlled. Especially, the change of the tip clearance and the clearance between rotors and stators are pointed out to be important design issues. The ATREX engine, which has shorter axial length and simpler rotor, has structural advantage over turbo jet.

  13. Expanding Metabolic Engineering Algorithms Using Feasible Space and Shadow Price Constraint Modules.

    PubMed

    Tervo, Christopher J; Reed, Jennifer L

    2014-12-01

    While numerous computational methods have been developed that use genome-scale models to propose mutants for the purpose of metabolic engineering, they generally compare mutants based on a single criteria (e.g., production rate at a mutant's maximum growth rate). As such, these approaches remain limited in their ability to include multiple complex engineering constraints. To address this shortcoming, we have developed feasible space and shadow price constraint (FaceCon and ShadowCon) modules that can be added to existing mixed integer linear adaptive evolution metabolic engineering algorithms, such as OptKnock and OptORF. These modules allow strain designs to be identified amongst a set of multiple metabolic engineering algorithm solutions that are capable of high chemical production while also satisfying additional design criteria. We describe the various module implementations and their potential applications to the field of metabolic engineering. We then incorporated these modules into the OptORF metabolic engineering algorithm. Using an Escherichia coli genome-scale model (iJO1366), we generated different strain designs for the anaerobic production of ethanol from glucose, thus demonstrating the tractability and potential utility of these modules in metabolic engineering algorithms. PMID:25478320

  14. Engine Company Evaluation of Feasibility of Aircraft Retrofit Water-Injected Turbomachines

    NASA Technical Reports Server (NTRS)

    Becker, Arthur

    2006-01-01

    This study supports the NASA Glenn Research Center and the U.S. Air Force Research Laboratory in their efforts to evaluate the effect of water injection on aircraft engine performance and emissions. In this study, water is only injected during the takeoff and initial climb phase of a flight. There is no water injection during engine start or ground operations, nor during climb, cruise, descent, or landing. This study determined the maintenance benefit of water injection during takeoff and initial climb and evaluated the feasibility of retrofitting a current production engine, the PW4062 (Pratt & Whitney, East Hartford, CT), with a water injection system. Predicted NO(x) emissions based on a 1:1 water-tofuel ratio are likely to be reduced between 30 to 60 percent in Environmental Protection Agency parameter (EPAP). The maintenance cost benefit for an idealized combustor water injection system installed on a PW4062 engine in a Boeing 747-400ER aircraft (The Boeing Company, Chicago, IL) is computed to be $22 per engine flight hour (EFH). Adding water injection as a retrofit kit would cost up to $375,000 per engine because of the required modifications to the fuel system and addition of the water supply system. There would also be significant nonrecurring costs associated with the development and certification of the system that may drive the system price beyond affordability.

  15. Estuary Live!!!

    NSDL National Science Digital Library

    Intended for elementary, middle, and high school students, this electronic estuary excursion, Estuary Live!!!, will take place May 8-12, 2000. Free to participants (but please sign up in advance), the field trip will explore the Rachel Carson Site of the North Carolina National Estuarine Research Reserve, covering four islands and salt marshes off the North Carolina coast. The site features useful educational materials, including a photo-illustrated field guide (of the "ecology, habitats and specific plants and animals found in North Carolina's estuaries"); lesson plans (covering highschool biology, estuary habitats, species interactions, and adaptations and communities); and a series of related links. The interactive field trip will require a java-enabled browser, RealVideo (to see a moving image and hear sound), and/or Chatvideo, to see a moving image, ask questions of the naturalist leading the trip, and receive responses via a chat window. Note that ChatVideo requires Netscape 4.0 or better and will not work with AOL or Internet Explorer, and pages "look best" on a screen with resolution of 800x600. The Estuary Live!!! Website is provided by the North Carolina National Estuarine Research Reserve Program, and The Center for Science, Mathematics and Technology Education at East Carolina University.

  16. Geothermal resource, engineering and economic feasibility study for the City of Ouray, Colorado. Final report

    SciTech Connect

    Meyer, R.T.; Raskin, R.; Zocholl, J.R.

    1982-07-31

    A geothermal energy feasibility study has been performed for the City of Ouray, Colorado, to determine the potential economic development opportunities to the City. The resource assessment indicates the resource to be associated with the Ouray fault zone, the Leadville limestone formation, the high thermal gradient in the area of the San Juan mountains, and the recharge from precipitation in the adjacent mountains. Four engineering designs of alternative sizes, costs, applications, and years of start-up have been defined to offer the City a range of development scales. Life cycle cost analyses have been conducted for cases of both public and private ownership. All systems are found to be feasible on both economic and technical grounds. 49 refs., 8 figs.

  17. Exploring Estuaries

    NSDL National Science Digital Library

    This site offers several ways to explore the importance of estuaries. Virtual tours of the Barataria-Terrebone Estuarine Complex and the Long Island Sound offer photos and text of each area explain their importance to humans, wildlife, and larger ecosystems. Additional resources for kids and adults are linked. A glossary page offers a list of vocabulary associated with estuaries. The site also offers a games and activities section for kids that has coloring sheets for young children, and inquiry-based interactive games for older kids. The games include a "Who Am I" animal identification game, and a game called "Solve a Mystery" where players must follow and investigation into what's wrong with an estuary, and make a decision on the cause of the problem. There are several possible mysteries to solve, each with a different solution.

  18. The electrochemical reduction of carbon dioxide to formate/formic acid: engineering and economic feasibility.

    PubMed

    Agarwal, Arun S; Zhai, Yumei; Hill, Davion; Sridhar, Narasi

    2011-09-19

    The engineering and economic feasibility of large-scale electrochemical reduction of carbon dioxide to formate salts and formic acid is the focus of this Full Paper. In our study we investigated the long-term performance of tin and other proprietary catalysts in the reduction of carbon dioxide to formate/formic acid at a gas/solid/liquid interface, using a flow-through reactor. The overall economics and energy consumption of the process are evaluated through a value chain analysis. The sensitivity of the net present value of the process to various process parameters is examined. PMID:21922681

  19. A hingeless rotor XV-15 design integration feasibility study. Volume 1: Engineering design studies

    NASA Technical Reports Server (NTRS)

    Magee, J. P.; Alexander, H. R.

    1978-01-01

    A design integration feasibility study was carried out to investigate what modifications to the basic XV-15 were necessary to accomplish a flight demonstration of the XV-15 with a Boeing hingeless rotor. Also investigated were additional modifications which would exploit the full capability provided by the combination of the new rotor and the existing T53 engine. An evaluation of the aircraft is presented and the data indicate improved air vehicle performance, acceptable aeroelastic margins, lower noise levels and improved flying qualities compared with the XV-15 aircraft. Inspection of the rotor system data provided shows an essentially unlimited life rotor for the flight spectrum anticipated for the XV-15.

  20. Idaho Nuclear Technology and Engineering Center Newly Generated Liquid Waste Demonstration Project Feasibility Study

    SciTech Connect

    Herbst, A.K.

    2000-02-01

    A research, development, and demonstration project for the grouting of newly generated liquid waste (NGLW) at the Idaho Nuclear Technology and Engineering Center is considered feasible. NGLW is expected from process equipment waste, decontamination waste, analytical laboratory waste, fuel storage basin waste water, and high-level liquid waste evaporator condensate. The potential grouted waste would be classed as mixed low-level waste, stabilized and immobilized to meet RCRA LDR disposal in a grouting process in the CPP-604 facility, and then transported to the state.

  1. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Microsoft Academic Search

    John Pratapas; Daniel Mather; Anton Kozlovsky

    2007-01-01

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control

  2. Modeling the Feasibility of Using Fuel Cells and Hydrogen Internal Combustion Engines in Remote Renewable Energy Systems: Preprint

    Microsoft Academic Search

    J. Cotrell; W. Pratt

    2003-01-01

    Recent advances in hydrogen fuel cell and internal combustion engine technologies have enabled new energy options for supplying electrical power in remote, off-grid areas. The objective of this investigation is to determine under which conditions wind turbines and PV systems can feasibly power electrolyzers to generate and store hydrogen for remote power generation using fuel cells and internal combustion engines.

  3. Feasibility analysis of an open cycle thermoacoustic engine with internal pulse combustion

    NASA Astrophysics Data System (ADS)

    Weiland, Nathan T.

    Thermoacoustic engines convert thermal energy into acoustic energy with few or no moving parts, thus they require little maintenance, are highly reliable, and are inexpensive to produce. These traits make them attractive for applications in remote or portable power generation, where a linear alternator converts the acoustic power into electric power. Their primary application, however, is in driving thermoacoustic refrigerators, which use acoustic power to provide cooling at potentially cryogenic temperatures, also without moving parts. This dissertation examines the feasibility of a new type of thermoacoustic engine, where mean flow and an internal pulse combustion process replace the hot heat exchanger in a traditional closed cycle thermoacoustic engine, thereby eliminating the heat exchanger's cost, inefficiency, and thermal expansion stresses. The theory developed in this work reveals that a large temperature difference must exist between the hot face of the regenerator and the hot combustion products flowing into it, and that much of the convective thermal energy input from the combustion process is converted into conductive and thermoacoustic losses in the regenerator. The development of the Thermoacoustic Pulse Combustion Engine, as described in this study, is designed to recover most of this lost thermal energy by routing the inlet pipes through the regenerator to preheat the combustion reactants. Further, the developed theory shows that the pulse combustion process has the potential to add up to 7% to the engine's acoustic power output for an acoustic pressure ratio of 10%, with linearly increasing contributions for increasing acoustic pressure ratios. Computational modeling and optimization of the Thermoacoustic Pulse Combustion Engine yield thermal efficiencies of about 20% for atmospheric mean operating pressures, though higher mean engine pressures increase this efficiency considerably by increasing the acoustic power density relative to the thermal losses. However, permissible mean engine pressures are limited by the need to avoid fouling the regenerator with condensation of water vapor out of the cold combustion products. Despite lower acoustic power densities, the Thermoacoustic Pulse Combustion Engine is shown to be well suited to portable refrigeration and power generation applications, due to its reasonable efficiency and inherent simplicity and compactness.

  4. GEEF: a geothermal engineering and economic feasibility model. Description and user's manual

    SciTech Connect

    Not Available

    1982-09-01

    The model is designed to enable decision makers to compare the economics of geothermal projects with the economics of alternative energy systems at an early stage in the decision process. The geothermal engineering and economic feasibility computer model (GEEF) is written in FORTRAN IV language and can be run on a mainframe or a mini-computer system. An abbreviated version of the model is being developed for usage in conjunction with a programmable desk calculator. The GEEF model has two main segments, namely (i) the engineering design/cost segment and (ii) the economic analysis segment. In the engineering segment, the model determines the numbers of production and injection wells, heat exchanger design, operating parameters for the system, requirement of supplementary system (to augment the working fluid temperature if the resource temperature is not sufficiently high), and the fluid flow rates. The model can handle single stage systems as well as two stage cascaded systems in which the second stage may involve a space heating application after a process heat application in the first stage.

  5. SAN FRANCISCO ESTUARY INSTITUTE CONTRIBUTION

    E-print Network

    on the Margins of San Francisco Bay Final Report An RMP Technical Report by Craig Jones Sea Engineering, Inc Estuary Institute #12;This report should be cited as: Jones, C., Yee, D., Davis J. A., McKee, L. J on the Margins of San Francisco Bay. Draft Report. An RMP Technical Report. Contribution No. 663. San Francisco

  6. Conceptual Design and Feasibility of Foil Bearings for Rotorcraft Engines: Hot Core Bearings

    NASA Technical Reports Server (NTRS)

    Howard, Samuel A.

    2007-01-01

    Recent developments in gas foil bearing technology have led to numerous advanced high-speed rotating system concepts, many of which have become either commercial products or experimental test articles. Examples include oil-free microturbines, motors, generators and turbochargers. The driving forces for integrating gas foil bearings into these high-speed systems are the benefits promised by removing the oil lubrication system. Elimination of the oil system leads to reduced emissions, increased reliability, and decreased maintenance costs. Another benefit is reduced power plant weight. For rotorcraft applications, this would be a major advantage, as every pound removed from the propulsion system results in a payload benefit.. Implementing foil gas bearings throughout a rotorcraft gas turbine engine is an important long-term goal that requires overcoming numerous technological hurdles. Adequate thrust bearing load capacity and potentially large gearbox applied radial loads are among them. However, by replacing the turbine end, or hot section, rolling element bearing with a gas foil bearing many of the above benefits can be realized. To this end, engine manufacturers are beginning to explore the possibilities of hot section gas foil bearings in propulsion engines. This overview presents a logical follow-on activity by analyzing a conceptual rotorcraft engine to determine the feasibility of a foil bearing supported core. Using a combination of rotordynamic analyses and a load capacity model, it is shown to be reasonable to consider a gas foil bearing core section. In addition, system level foil bearing testing capabilities at NASA Glenn Research Center are presented along with analysis work being conducted under NRA Cooperative Agreements.

  7. Feasibility Demonstration of a 445N High-Performance Rocket Engine

    NASA Technical Reports Server (NTRS)

    Appel, Marshall A.; Schoenman, Leonard; Franklin, Jerrold E.; Lansaw, P. Tina

    1989-01-01

    A program to demonstrate the feasibility of a high-performance 445 Newton (100 lb(sub f)) NTO/NMH rocket engine is presented. An existing high-performance injector was coupled with three different thrust chambers to acquire test data for the program. A stainless-steel sea-level chamber was used for test stand checkout, calibration and initial injector performance determinations. Two high-temperature iridium lined rhenium thrust chambers were used to determine altitude performance and durability. The first chamber was tested for a total duration of 3381 s and the second was tested for a total duration of 15,000 s with no measurable degradation. Extrapolation of epsilon = 44:1 experimental data to the recommended epsilon = 467:1 expansion nozzle, using the JANNAF methodology, showed that a performance of 3138 to 3167 N-s/kg (320 to 323 lb(sub f-s)/lb(sub m) could be achieved with the present design. Recommendations are presented which would allow a redesigned engine to achieve the 3195 N-s/kg (326 lb(sub f-s)/lb(sub m)) program goal.

  8. Engineering Feasibility and Trade Studies for the NASA/VSGC MicroMaps Space Mission

    NASA Technical Reports Server (NTRS)

    Abdelkhalik, Ossama O.; Nairouz, Bassem; Weaver, Timothy; Newman, Brett

    2003-01-01

    Knowledge of airborne CO concentrations is critical for accurate scientific prediction of global scale atmospheric behavior. MicroMaps is an existing NASA owned gas filter radiometer instrument designed for space-based measurement of atmospheric CO vertical profiles. Due to programmatic changes, the instrument does not have access to the space environment and is in storage. MicroMaps hardware has significant potential for filling a critical scientific need, thus motivating concept studies for new and innovative scientific spaceflight missions that would leverage the MicroMaps heritage and investment, and contribute to new CO distribution data. This report describes engineering feasibility and trade studies for the NASA/VSGC MicroMaps Space Mission. Conceptual studies encompass: 1) overall mission analysis and synthesis methodology, 2) major subsystem studies and detailed requirements development for an orbital platform option consisting of a small, single purpose spacecraft, 3) assessment of orbital platform option consisting of the International Space Station, and 4) survey of potential launch opportunities for gaining assess to orbit. Investigations are of a preliminary first-order nature. Results and recommendations from these activities are envisioned to support future MicroMaps Mission design decisions regarding program down select options leading to more advanced and mature phases.

  9. CARS temperature measurements in the fuel preburner of the Space Shuttle main engine: A feasibility study

    NASA Technical Reports Server (NTRS)

    Beiting, E. J.; Luthe, J. C.

    1983-01-01

    This report discusses the feasibility of making temperature profile measurements in the fuel preburner of the main engine of the space shuttle (SSME) using coherent anti-Stokes Raman spectroscopy (CARS). The principal thrust of the work is to identify problems associated with making CARS measurements in high temperature gas phase hydrogen at very high pressures (approx 400 atmospheres). To this end a theoretical study was made of the characteristics of the CAR spectra of H2 as a function of temperature and pressure and the accuracy with which temperatures can be extracted from this spectra. In addition the experimental problems associated with carrying out these measurements on a SSME at NSTL were identified. A conceptual design of a CARS system suitable for this work is included. Many of the results of the calculations made in this report are plotted as a function of temperature. In the course of presenting these results, it was necessary to decide whether the number of density or the pressure should be treated as a fixed parameter.

  10. A feasibility study on using inkjet technology, micropumps, and MEMs as fuel injectors for bipropellant rocket engines

    NASA Astrophysics Data System (ADS)

    Glynne-Jones, Peter; Coletti, M.; White, N. M.; Gabriel, S. B.; Bramanti, C.

    2010-07-01

    Control over drop size distributions, injection rates, and geometrical distribution of fuel and oxidizer sprays in bi-propellant rocket engines has the potential to produce more efficient, more stable, less polluting rocket engines. This control also offers the potential of an engine that can be throttled, working efficiently over a wide range of output thrusts. Inkjet printing technologies, MEMS fuel atomizers, and piezoelectric injectors similar in concept to those used in diesel engines are considered for their potential to yield a new, more active injection scheme for a rocket engine. Inkjets are found to be unable to pump at sufficient pressures, and have possibly dangerous failure modes. Active injection is found to be feasible if high pressure drop along the injector plate is used. A conceptual design is presented and its basic behavior assessed.

  11. Introduction to Estuaries

    EPA Science Inventory

    Estuaries, although minor geographical features at the global scale, have major importance for society and the world?s economies. This chapter introduces estuaries by presenting an overview of definitions, origins, physical, chemical and ecological attributes, and the interaction...

  12. PHYSICAL REVIEW B 84, 245211 (2011) Feasibility of band gap engineering of pyrite FeS2

    E-print Network

    Ceder, Gerbrand

    PHYSICAL REVIEW B 84, 245211 (2011) Feasibility of band gap engineering of pyrite FeS2 Ruoshi Sun-principles computations to investigate whether the band gap of pyrite FeS2 can be increased by alloying in order to make in the pyrite structure than FeS2. Practical band gap enhancement is observed only in the Ru and Os alloyed

  13. Feasibility Study of a Pressure-fed Engine for a Water Recoverable Space Shuttle Booster

    NASA Technical Reports Server (NTRS)

    Gerstl, E.

    1972-01-01

    Detailed mass properties are presented for a gimbaled, fixed thrust, regeneratively cooled engine having a coaxial pintle injector. The baseline design parameters for this engine are tabulated. Mass properties are also summarized for several other engine configurations i.e., a hinge nozzle using a Techroll seal, a gimbaled duct cooled engine and a regeneratively cooled engine using liquid injection thrust vector control (LITVC). Detailed engine analysis and design trade studies leading to the selection of a regeneratively cooled gimbaled engine and pertaining to the selection of the baseline design configuration are also given.

  14. Embedded Acoustic Sensor Array for Engine Fan Noise Source Diagnostic Test: Feasibility of Noise Telemetry via Wireless Smart Sensors

    NASA Technical Reports Server (NTRS)

    Zaman, Afroz; Bauch, Matthew; Raible, Daniel

    2011-01-01

    Aircraft engines have evolved into a highly complex system to meet ever-increasing demands. The evolution of engine technologies has primarily been driven by fuel efficiency, reliability, as well as engine noise concerns. One of the sources of engine noise is pressure fluctuations that are induced on the stator vanes. These local pressure fluctuations, once produced, propagate and coalesce with the pressure waves originating elsewhere on the stator to form a spinning pressure pattern. Depending on the duct geometry, air flow, and frequency of fluctuations, these spinning pressure patterns are self-sustaining and result in noise which eventually radiate to the far-field from engine. To investigate the nature of vane pressure fluctuations and the resulting engine noise, unsteady pressure signatures from an array of embedded acoustic sensors are recorded as a part of vane noise source diagnostics. Output time signatures from these sensors are routed to a control and data processing station adding complexity to the system and cable loss to the measured signal. "Smart" wireless sensors have data processing capability at the sensor locations which further increases the potential of wireless sensors. Smart sensors can process measured data locally and transmit only the important information through wireless communication. The aim of this wireless noise telemetry task was to demonstrate a single acoustic sensor wireless link for unsteady pressure measurement, and thus, establish the feasibility of distributed smart sensors scheme for aircraft engine vane surface unsteady pressure data transmission and characterization.

  15. Welcome to Estuaries

    NSDL National Science Digital Library

    This resource features three sections devoted to learning about estuaries: an online tutorial, an educational roadmap to resources, and formal lesson plans. The tutorial shows how estuaries are classified by their geology and water circulation patterns, the various ecosystem services estuaries perform, how organisms have adapted to the unique environmental conditions found in estuaries, the many disturbances that estuaries face from nature and human activities, and finally, the essential work that the National Estuarine Research Reserve System and its many partners conduct to monitor, preserve, and restore estuarine ecosystems throughout the United States. The roadmap to resources provides a set of links to specific data related to the information presented in the tutorial. Lesson plans on estuaries are also provided.

  16. ENGINEERING & GINNING Feasibility of Applying Seedcotton Cleaning Principles to Lint Cleaning

    Microsoft Academic Search

    Gino J. Mangialardi Jr; W. Stanley Anthony

    2000-01-01

    Cotton (Gossypium hirsutum L.) fibers are cleaned at gins with saw-type lint cleaners to improve the market value, but the aggressive saws sometimes harm the quality of the fiber. Cleaners for seedcotton are less aggressive than saw-type cleaners. In an attempt to improve fiber quality during ginning, experiments were conducted to evaluate the feasibility of cleaning lint by applying principles

  17. Feasibility, engineering aspects and physics reach of microwave cavity experiments searching for hidden photons and axions

    E-print Network

    Fritz Caspers; Joerg Jaeckel; Andreas Ringwald

    2009-08-07

    Using microwave cavities one can build a resonant ``light-shining-through-walls'' experiment to search for hidden sector photons and axion like particles, predicted in many extensions of the standard model. In this note we make a feasibility study of the sensitivities which can be reached using state of the art technology.

  18. Regional Differences Among Estuaries

    NSDL National Science Digital Library

    Oberrecht, Kenn

    This text discusses differences in estuaries in different regions of the United States. It contrasts the fjord-like estuaries of the rocky Maine coast with the sandy barrier beaches, islands, and enclosed bays and sounds further south. The site also calls attention to the difference between the East Coast and the Northwest coast of emergence. The point is made that although they differ, all estuaries have great value and many are in danger.

  19. Learning Lessons from Estuaries

    ERIC Educational Resources Information Center

    Schnittka, Christine

    2006-01-01

    There is something that draws all people to the sea and especially to the fertile estuaries that nuzzle up to its shores. An estuary serves as both a nursery and a grave for sea creatures. If life evolved from some primordial sea, it may well have been an estuary--a place where ocean and rivers meet and fresh and salty waters mingle in the…

  20. Nutrients in an Estuary

    NSDL National Science Digital Library

    TERC

    2012-06-26

    In this activity, learners model estuaries, artificially enriching both fresh and salt water samples with different amounts of nutrients and observing the growth of algae over several weeks. Learners relate their results to the phenomenon of algae blooms in estuaries. Learners then analyze data for different sites at the Guana Tolomato Matanzas National Estuarine Research Reserve (GTMNERR) in Florida to discover the relationships between nitrogen, chlorophyll, and dissolved oxygen. Finally, learners study how nutrients cycle through an estuary and suggest recommendations for reducing nutrient inputs to estuary waters.

  1. CF6 jet engine performance improvement program. Task 1: Feasibility analysis

    NASA Technical Reports Server (NTRS)

    Fasching, W. A.

    1979-01-01

    Technical and economic engine improvement concepts selected for subsequent development include: (1) fan improvement; (2) short core exhaust; (3) HP turbine aerodynamic improvement; (4) HP turbine roundness control; (5) HP turbine active clearance control; and (6) cabin air recirculation. The fuel savings for the selected engine modification concepts for the CF6 fleet are estimated.

  2. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    SciTech Connect

    John Pratapas; Daniel Mather; Anton Kozlovsky

    2007-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen's significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an analysis of test results indicates that hydrogen enhanced natural gas HCCI (versus neat natural gas HCCI at comparable stoichiometry) had the following characteristics: (1) Substantially lower intake temperature needed for stable HCCI combustion; (2) Inconclusive impact on engine BMEP and power produced; (3) Small reduction in the thermal efficiency of the engine; (4) Moderate reduction in the unburned hydrocarbons in the exhaust; (5) Slight increase in NOx emissions in the exhaust; (6) Slight reduction in CO2 in the exhaust; and (7) Increased knocking at rich stoichiometry. The major accomplishments and findings from the project can be summarized as follows: (1) A model was calibrated for accurately predicting heat release rate and peak pressures for HCCI combustion when operating on hydrogen and natural gas blends. (2) A single cylinder research engine was thoroughly mapped to compare performance and emissions for micro-pilot natural gas compression ignition, and HCCI combustion for neat natural gas versus blends of natural gas and hydrogen. (3) The benefits of using hydrogen to extend, up to a limit, the stable operating window for HCCI combustion of natural gas at higher intake pressures, leaner air to fuel ratios or lower inlet temperatures was documented.

  3. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    SciTech Connect

    Pratapas, John; Mather, Daniel; Kozlovsky, Anton

    2013-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen’s significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an analysis of test results indicates that hydrogen enhanced natural gas HCCI (versus neat natural gas HCCI at comparable stoichiometry) had the following characteristics: • Substantially lower intake temperature needed for stable HCCI combustion • Inconclusive impact on engine BMEP and power produced, • Small reduction in the thermal efficiency of the engine, • Moderate reduction in the unburned hydrocarbons in the exhaust, • Slight increase in NOx emissions in the exhaust, • Slight reduction in CO2 in the exhaust. • Increased knocking at rich stoichiometry The major accomplishments and findings from the project can be summarized as follows: 1. A model was calibrated for accurately predicting heat release rate and peak pressures for HCCI combustion when operating on hydrogen and natural gas blends. 2. A single cylinder research engine was thoroughly mapped to compare performance and emissions for micro-pilot natural gas compression ignition, and HCCI combustion for neat natural gas versus blends of natural gas and hydrogen.

  4. National Estuary Program

    NSDL National Science Digital Library

    Estuaries are places where rivers meet the sea and are critical to the health of coastal environments and our enjoyment of them. Website features abundant information on the legal and scientific aspects of estuary preservation. Includes guidelines, program profiles, and a shorter version in Spanish. Resources for teachers and students include games and activities. External links to additional programs also provided.

  5. DYNAMIC ESTUARY MODEL PERFORMANCE

    EPA Science Inventory

    Applications of the Dynamic Estuary Model (DEM) to both the Delaware and Potomac Estuaries by the Environmental Protection Agency during the 1970s are summarized and evaluated. Methods for calibrating, refining, and validating this model, and statistics for evaluating its perform...

  6. Estuary Data Mapper

    EPA Science Inventory

    The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary has three elements: an estuarine geo-referenced relational database, watershed GIS coverages, and tools to support decision-making. To facilita...

  7. Experimental research made during a city cycle on the feasibility of electrically charged SI engines

    NASA Astrophysics Data System (ADS)

    Kocsis, Levente; Burnete, Nicolae

    2014-06-01

    The paper presents experimental research on performance improvements in a city cycle (operating mostly transient) of a compact class vehicle equipped with a turbocharged SI engine which had attached an electric charger, to improve engine response at low operational speeds. During tests, functional parameters, energy consumption of the electric charger and vehicle performances were measured while driving in two operating conditions: with active and inactive electric charger. The tests were carried out on a well-defined path, in the same driving style, by the same driver.

  8. A Feasibility Study of Reciprocating-Flow Super-Adiabatic Combustion Engine

    NASA Astrophysics Data System (ADS)

    Hanamura, Katsunori; Nishio, Satoshi

    Super-adiabatic combustion engine proposed here has a high thermal efficiency of 57.5% over a wide range of operation conditions. The engine consists of a displacer piston, a power piston and a porous medium in a cylinder. These create reciprocating motions with a phase relation angle. After scavenging, a mixture introduced is compressed by the displacer piston and preheated by the porous medium, and then, ignited in the vicinity of the downstream end of the porous medium. The main reaction occurs in the power piston side cylinder. By the heat recirculation from the residual combustion-gas enthalpy to the enthalpy increase in the mixture, the maximum temperature becomes higher than the theoretical (adiabatic) flame temperature. As a result, the system has such a high thermal efficiency and extends the flammability limit to a concentration of 1.58vol.% methane in air.

  9. JT8D and JT9D jet engine performance improvement program. Task 1: Feasibility analysis

    NASA Technical Reports Server (NTRS)

    Gaffin, W. O.; Webb, D. E.

    1979-01-01

    JT8D and JT9D component performance improvement concepts which have a high probability of incorporation into production engines were identified and ranked. An evaluation method based on airline payback period was developed for the purpose of identifying the most promising concepts. The method used available test data and analytical models along with conceptual/preliminary designs to predict the performance improvements, weight, installation characteristics, cost for new production and retrofit, maintenance cost, and qualitative characteristics of candidate concepts. These results were used to arrive at the concept payback period, which is the time required for an airline to recover the investment cost of concept implementation.

  10. Boron neutron capture therapy applied to advanced breast cancers: Engineering simulation and feasibility study of the radiation treatment protocol

    NASA Astrophysics Data System (ADS)

    Sztejnberg Goncalves-Carralves, Manuel Leonardo

    This dissertation describes a novel Boron Neutron Capture Therapy (BNCT) application for the treatment of human epidermal growth factor receptor type 2 positive (HER2+) breast cancers. The original contribution of the dissertation is the development of the engineering simulation and the feasibility study of the radiation treatment protocol for this novel combination of BNCT and HER2+ breast cancer treatment. This new concept of BNCT, representing a radiation binary targeted treatment, consists of the combination of two approaches never used in a synergism before. This combination may offer realistic hope for relapsed and/or metastasized breast cancers. This treatment assumes that the boronated anti-HER2 monoclonal antibodies (MABs) are administrated to the patient and accumulate preferentially in the tumor. Then the tumor is destroyed when is exposed to neutron irradiation. Since the use of anti-HER2 MABs yields good and promising results, the proposed concept is expected to amplify the known effect and be considered as a possible additional treatment approach to the most severe breast cancers for patients with metastasized cancer for which the current protocol is not successful and for patients refusing to have the standard treatment protocol. This dissertation makes an original contribution with an integral numerical approach and proves feasible the combination of the aforementioned therapy and disease. With these goals, the dissertation describes the theoretical analysis of the proposed concept providing an integral engineering simulation study of the treatment protocol. An extensive analysis of the potential limitations, capabilities and optimization factors are well studied using simplified models, models based on real CT patients' images, cellular models, and Monte Carlo (MCNP5/X) transport codes. One of the outcomes of the integral dosimetry assessment originally developed for the proposed treatment of advanced breast cancers is the implementation of BNCT for HER2+ breast cancers for deep seated tumors using MITRII-FCB facility with an 8 cm diameter beam (port closest-to-tumor position), with boron concentrations in the tumor higher than 32 mug/g, and for a tumor-to-healthy tissue boron concentration ratio of 8:1. The therapeutic ratios for the proposed treatment would be higher than five for skin and adipose tissue and higher than three for tumor surrounding fibroglandular tissue. The microdosimetry study shows potential improvements in the therapeutic ratios based on the expected sub-cellular boron biodistributions. The engineering simulation study of clinical cases shows the advantages of using BNCT for HER+ breast cancers. Assuming an assured high efficiency of the boron agent delivery, the proposed concept can be considered for stage IV HER2+ breast cancers in treating the metastasized tumors in brain, head and neck, and lungs.

  11. Feasibility of using a high-level waste canister as an engineered barrier in disposal

    SciTech Connect

    Slate, S.C.; Pitman, S.G.; Nesbitt, J.F.; Partain, W.L.

    1982-08-01

    The objective of this report is to evaluate the feasibility of designing a process canister that could also serve as a barrier canister. To do this a general set of performance criteria is assumed and several metal alloys having a high probability of demonstrating high corrosion resistance under repository conditions are evaluated in a qualitative design assessment. This assessment encompasses canister manufacture, the glass-filling process, interim storage, transportation, and to a limited extent, disposal in a repository. A series of scoping tests were carried out on two titanium alloys and Inconel 625 to determine if the high temperature inherent in the glass-fill processing would seriously affect either the strength or corrosion resistance of these metals. This is a process-related concern unique to the barrier canister concept. The material properties were affected by the heat treatments which simulated both the joule-heated glass melter process (titanium alloys and Inconel 625) and the in-can melter (ICM) process (Inconel 625). However, changes in the material properties were generally within 20% of the original specimens. Accelerated corrosion testing of the heat treated coupons in a highly oxygenated brine showed basic corrosion resistance of titanium grade 12 and Inconel 625 to compare favorably with that of the untreated coupons. The titanium grade 2 coupons experienced severe corrosion pitting. These corrosion tests were of a scoping nature and suitable primarily for the detection of gross sensitivity to the heat treatment inherent in the glass-fill process. They are only suggstive of repository performance since the tests do not adequately model the wide range of repository conditions that could conceivably occur.

  12. Engineering practice variation through provider agreement: a cluster-randomized feasibility trial

    PubMed Central

    McCarren, Madeline; Twedt, Elaine L; Mansuri, Faizmohamed M; Nelson, Philip R; Peek, Brian T

    2014-01-01

    Purpose Minimal-risk randomized trials that can be embedded in practice could facilitate learning health-care systems. A cluster-randomized design was proposed to compare treatment strategies by assigning clusters (eg, providers) to “favor” a particular drug, with providers retaining autonomy for specific patients. Patient informed consent might be waived, broadening inclusion. However, it is not known if providers will adhere to the assignment or whether institutional review boards will waive consent. We evaluated the feasibility of this trial design. Subjects and methods Agreeable providers were randomized to “favor” either hydrochlorothiazide or chlorthalidone when starting patients on thiazide-type therapy for hypertension. The assignment applied when the provider had already decided to start a thiazide, and providers could deviate from the strategy as needed. Prescriptions were aggregated to produce a provider strategy-adherence rate. Results All four institutional review boards waived documentation of patient consent. Providers (n=18) followed their assigned strategy for most of their new thiazide prescriptions (n=138 patients). In the “favor hydrochlorothiazide” group, there was 99% adherence to that strategy. In the “favor chlorthalidone” group, chlorthalidone comprised 77% of new thiazide starts, up from 1% in the pre-study period. When the assigned strategy was followed, dosing in the recommended range was 48% for hydrochlorothiazide (25–50 mg/day) and 100% for chlorthalidone (12.5–25.0 mg/day). Providers were motivated to participate by a desire to contribute to a comparative effectiveness study. A study promotional mug, provider information letter, and interactions with the site investigator were identified as most helpful in reminding providers of their study drug strategy. Conclusion Providers prescribed according to an assigned drug-choice strategy most of the time for the purpose of a comparative effectiveness study. This simple design could facilitate research participation and behavior change in non-research clinicians. Waiver of patient consent can broaden the representation of patients, providers, and settings. PMID:25414573

  13. Restore America's Estuaries

    NSDL National Science Digital Library

    This non-profit organization promotes the restoration and protection of America's estuaries. Projects encompass scientific research, education and community-based action, including restoration by school youngsters, as well as policy initiatives at the national level. An introduction to estuaries contains concise definitions, value in ecology and economics, current threats, and elements of restoration. Also offers: links to educational resources; news and photo gallery; a CD-rom guide to estuarine restoration.

  14. Strategy for assessing the technical, environmental, and engineering feasibility of subseabed disposal

    SciTech Connect

    Anderson, D.R.; Talbert, D.M.; Reese, D.; Boyer, D.G.; Herrmann, H.; Kelly, J.

    1980-07-01

    This report presents the strategy and management techniques used in the development of the US Subseabed Disposal Program (SDP) for possible disposal of both high-level waste and spent fuel. These have been developed through joint efforts of the Department of Energy (DOE), Division of Waste Isolation, the Sandia Technical Program Manager, the Technical Program Coordinators, the Advisory Group, and the Principal Investigators. Three subsections of this paper address the various components which make up the SDP strategy and management techniques. The first section summarizes the US DOE high-level waste and spent-fuel disposal program and the position that the SDP occupies within that program. The second section, the Subseabed Program Plan, addresses the technical and administrative tools which are employed to facilitate the day-to-day operation of the SDP. The third section addresses the current studies and future plans for addressing the legal, political, and international uncertainties that must be resolved before the SDP reaches the final engineering phases.

  15. Feasibility of ceramic-polymer composite cryogels as scaffolds for bone tissue engineering.

    PubMed

    Rodriguez-Lorenzo, Luis M; Saldaña, Laura; Benito-Garzón, Lorena; García-Carrodeguas, Raul; de Aza, Salvador; Vilaboa, Nuria; Román, Julio San

    2012-06-01

    The purpose of the current study was to investigate whether the cryopolymerization technique is capable of producing suitable scaffolds for bone tissue engineering. Cryopolymers made of 2-hydroxyethyl methacrylate and acrylic acid with (W1 and W20) and without (W0) wollastonite particles were prepared. The elastic modulus of the specimens rose one order of magnitude from W1 to W20. Total porosity reached 56% for W0, 72% for W1 and 36% for W20, with pore sizes of up to 2 mm, large interconnection sizes of up to 1 mm and small interconnection sizes of 50-80 µm on dry specimens. Cryogels swell up to 224 ± 17% for W0, 315 ± 18% for W1 and 231 ± 27% for W20 specimens, while maintaining the integrity of the bodies. Pore sizes > 5 mm can be observed for swollen specimens. The biocompatibility of the samples was tested using human mesenchymal stem cells isolated from bone marrow and adipose tissues. Both types of cells attached and grew on the three tested substrates, colonized their inner regions and organized an extracellular cell matrix. Fibronectin and osteopontin levels decreased in the media from cells cultured on W20 samples, likely due to increased binding on the ECM deposited by cells. The osteoprotegerin-to-receptor activator of nuclear factor-?B ligand secretion ratios increased with increasing wollastonite content. Altogether, these results indicate that an appropriate balance of surface properties and structure that favours stromal cell colonization in the porous cryogels can be achieved by modulating the amount of wollastonite. PMID:21800433

  16. Estuarine Science: All About Estuaries

    NSDL National Science Digital Library

    Estuaries are partially enclosed bodies of water along coastlines where fresh water and salt water meet and mix. They act as a transition zone between oceans and continents. This site examines various aspects of estuaries, focusing on the geological features that make an estuary, as well as the water circulation patterns by which they are classified. It also has a section that allows the user to access additional text and graphics on many of the estuaries of the world.

  17. Feasibility of Conducting J-2X Engine Testing at the Glenn Research Center Plum Brook Station B-2 Facility

    NASA Technical Reports Server (NTRS)

    Schafer, Charles F.; Cheston, Derrick J.; Worlund, Armis L.; Brown, James R.; Hooper, William G.; Monk, Jan C.; Winstead, Thomas W.

    2008-01-01

    A trade study of the feasibility of conducting J-2X testing in the Glenn Research Center (GRC) Plum Brook Station (PBS) B-2 facility was initiated in May 2006 with results available in October 2006. The Propulsion Test Integration Group (PTIG) led the study with support from Marshall Space Flight Center (MSFC) and Jacobs Sverdrup Engineering. The primary focus of the trade study was on facility design concepts and their capability to satisfy the J-2X altitude simulation test requirements. The propulsion systems tested in the B-2 facility were in the 30,000-pound (30K) thrust class. The J-2X thrust is approximately 10 times larger. Therefore, concepts significantly different from the current configuration are necessary for the diffuser, spray chamber subsystems, and cooling water. Steam exhaust condensation in the spray chamber is judged to be the key risk consideration relative to acceptable spray chamber pressure. Further assessment via computational fluid dynamics (CFD) and other simulation capabilities (e.g. methodology for anchoring predictions with actual test data and subscale testing to support investigation.

  18. Fault detection for salinity sensors in the Columbia estuary Cynthia Archer

    E-print Network

    Leen, Todd K.

    Fault detection for salinity sensors in the Columbia estuary Cynthia Archer Department of Computer, salinity measurement Citation: Archer, C., A. Baptista, and T. K. Leen, Fault detection for salinity [U.S. Army Corps of Engineers, 2001]. [3] CORIE salinity sensors deployed in the harsh estuary

  19. Feasibility study of using the RoboEarth cloud engine for rapid mapping and tracking with small unmanned aerial systems

    NASA Astrophysics Data System (ADS)

    Li-Chee-Ming, J.; Armenakis, C.

    2014-11-01

    This paper presents the ongoing development of a small unmanned aerial mapping system (sUAMS) that in the future will track its trajectory and perform 3D mapping in near-real time. As both mapping and tracking algorithms require powerful computational capabilities and large data storage facilities, we propose to use the RoboEarth Cloud Engine (RCE) to offload heavy computation and store data to secure computing environments in the cloud. While the RCE's capabilities have been demonstrated with terrestrial robots in indoor environments, this paper explores the feasibility of using the RCE in mapping and tracking applications in outdoor environments by small UAMS. The experiments presented in this work assess the data processing strategies and evaluate the attainable tracking and mapping accuracies using the data obtained by the sUAMS. Testing was performed with an Aeryon Scout quadcopter. It flew over York University, up to approximately 40 metres above the ground. The quadcopter was equipped with a single-frequency GPS receiver providing positioning to about 3 meter accuracies, an AHRS (Attitude and Heading Reference System) estimating the attitude to about 3 degrees, and an FPV (First Person Viewing) camera. Video images captured from the onboard camera were processed using VisualSFM and SURE, which are being reformed as an Application-as-a-Service via the RCE. The 3D virtual building model of York University was used as a known environment to georeference the point cloud generated from the sUAMS' sensor data. The estimated position and orientation parameters of the video camera show increases in accuracy when compared to the sUAMS' autopilot solution, derived from the onboard GPS and AHRS. The paper presents the proposed approach and the results, along with their accuracies.

  20. Baseline Ecological Risk Assessment of the Calcasieu Estuary, Louisiana: Part 1. Overview and Problem Formulation

    Microsoft Academic Search

    Donald D. MacDonald; Dwayne R. J. Moore; Christopher G. Ingersoll; Dawn E. Smorong; R. Scott Carr; Ron Gouguet; David Charters; Duane Wilson; Tom Harris; Jon Rauscher; Susan Roddy; John Meyer

    2011-01-01

    A remedial investigation\\/feasibility study (RI\\/FS) of the Calcasieu Estuary cooperative site was initiated in 1998. This site,\\u000a which is located in the southwestern portion of Louisiana in the vicinity of Lake Charles, includes the portion of the estuary\\u000a from the saltwater barrier on the Calcasieu River to Moss Lake. As part of the RI\\/FS, a baseline ecological risk assessment\\u000a (BERA)

  1. Ecology of estuaries

    SciTech Connect

    Kennish, M.J.

    1986-01-01

    This book is a summary of information available on estuarine ecology, that reviews concepts and problems of estuaries and assesses the value of these coastal systems. It investigates such topics as water circulation and mixing, trace elements, nutrients, organic matter, and sedimentary processes, with reviews on more than two decades of intense study. Chapters reflect contributions from a variety of interdisciplinary sciences including botany, chemistry, ecology, geology, physics, and zoology.

  2. Burrowing shrimp as foundation species in NE Pacific estuaries

    EPA Science Inventory

    My talk will be about the my research to characterize the role that burrowing shrimp play as foundation/engineering species in Pacific NW estuaries. My research has focused on measuring the abundance & distribution of two species (ghost shrimp & mud shrimp) at ecosystem scales, ...

  3. IEEE TRANSACTIONS ON NEURAL SYSTEMS AND REHABILITATION ENGINEERING, VOL. 15, NO. 2, JUNE 2007 295 Feasibility of Prosthetic Posture Sensing

    E-print Network

    Loeb, Gerald E.

    Feasibility of Prosthetic Posture Sensing Via Injectable Electronic Modules Wei Tan, Member, IEEE, and Gerald developed for functional electric stimulation (FES) to reanimate paralyzed limbs. This paper investigates-and-grasp tasks. A sensor fusion step is proposed to estimate the position and orientation of a limb segment using

  4. Engineering and economic feasibility of using poultry litter as a fuel to generate electric power at Maryland`s Eastern Correctional Institute

    SciTech Connect

    Estomin, S.L.; Walters, G.; Prasad, A.; Ross, J.

    1998-02-16

    This report presents an analysis of the engineering, environmental, and economic feasibility of the Eastern Correctional Institute (ECI) meeting its electric power and thermal requirements by relying on poultry litter as a fuel. In addition to satisfying all or a portion of the utility requirements of ECI, a maximum/medium security prison located in Princess Anne, Maryland, the use of poultry litter as a fuel would reduce the amount of poultry waste currently used on the Eastern Shore as fertilizer. Based on the engineering and environmental assessments conducted, three alternative scenarios to satisfy ECI`s electric power supply and thermal requirements using poutlry litter as a fuel were developed. For all scenarios, as well as a base case defined by current operations at ECI, 20-year life-cycle costs were estimated based on projections of usage, capital costs, fuel costs, labor costs, and other relevant factors.

  5. Estuaries of South Africa

    NASA Astrophysics Data System (ADS)

    Allanson, Brian; Baird, Dan

    1999-05-01

    Estuaries of South Africa presents an authoritative and comprehensive review of the current status of that country's estuarine research and management. Contributors provide information on a wide range of topics, including geological, physical and chemical processes; diversity and productivity of plant and animal communities; interactions among estuarine organisms; and system properties, ecological modeling and current management issues. This broad scope is complemented by a comparative perspective, resulting in a volume that provides a unique contribution to the subject of estuarine ecology. This volume is relevant to all those working in this field throughout the world.

  6. A feasibility study of dynamic stress analysis inside a running internal combustion engine using synchrotron X-ray beams.

    PubMed

    Baimpas, Nikolaos; Drakopoulos, Michael; Connolley, Thomas; Song, Xu; Pandazaras, Costas; Korsunsky, Alexander M

    2013-03-01

    The present investigation establishes the feasibility of using synchrotron-generated X-ray beams for time-resolved in situ imaging and diffraction of the interior components of an internal combustion engine during its operation. The demonstration experiment was carried out on beamline I12 (JEEP) at Diamond Light Source, UK. The external hutch of the JEEP instrument is a large-scale engineering test bed for complex in situ processing and simulation experiments. The hutch incorporates a large capacity translation and rotation table and a selection of detectors for monochromatic and white-beam diffraction and imaging. These capabilities were used to record X-ray movies of a motorcycle internal combustion engine running at 1850 r.p.m. and to measure strain inside the connecting rod via stroboscopic X-ray diffraction measurement. The high penetrating ability and high flux of the X-ray beam at JEEP allowed the observation of inlet and outlet valve motion, as well as that of the piston, connecting rod and the timing chain within the engine. Finally, the dynamic internal strain within the moving connecting rod was evaluated with an accuracy of ~50 × 10(-6). PMID:23412489

  7. DC-9/JT8D refan, Phase 1. [technical and economic feasibility of retrofitting DC-9 aircraft with refan engine to achieve desired acoustic levels

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Analyses and design studies were conducted on the technical and economic feasibility of installing the JT8D-109 refan engine on the DC-9 aircraft. Design criteria included minimum change to the airframe to achieve desired acoustic levels. Several acoustic configurations were studied with two selected for detailed investigations. The minimum selected acoustic treatment configuration results in an estimated aircraft weight increase of 608 kg (1,342 lb) and the maximum selected acoustic treatment configuration results in an estimated aircraft weight increase of 809 kg (1,784 lb). The range loss for the minimum and maximum selected acoustic treatment configurations based on long range cruise at 10 668 m (35,000 ft) altitude with a typical payload of 6 804 kg (15,000 lb) amounts to 54 km (86 n. mi.) respectively. Estimated reduction in EPNL's for minimum selected treatment show 8 EPNdB at approach, 12 EPNdB for takeoff with power cutback, 15 EPNdB for takeoff without power cutback and 12 EPNdB for sideline using FAR Part 36. Little difference was estimated in EPNL between minimum and maximum treatments due to reduced performance of maximum treatment. No major technical problems were encountered in the study. The refan concept for the DC-9 appears technically feasible and economically viable at approximately $1,000,000 per airplane. An additional study of the installation of JT3D-9 refan engine on the DC-8-50/61 and DC-8-62/63 aircraft is included. Three levels of acoustic treatment were suggested for DC-8-50/61 and two levels for DC-8-62/63. Results indicate the DC-8 technically can be retrofitted with refan engines for approximately $2,500,000 per airplane.

  8. Dissolved oxygen in two Oregon estuaries: Importance of the ocean-estuary connection

    EPA Science Inventory

    We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

  9. Dissolved oxygen in two Oregon estuaries: Importance of the ocean-estuary connection - March 2011

    EPA Science Inventory

    We examined the role of the ocean?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO w...

  10. Dissolved oxygen in two Oregon estuaries: The importance of the ocean-estuary connection

    EPA Science Inventory

    We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

  11. Estuaries and Clean Water Act of 2000

    NSDL National Science Digital Library

    The Office of Water at the Environmental Protection Agency has posted online this document on the new Estuaries and Clean Water Act of 2000. Available in .pdf format, the document summarizes the Act, which emphasizes restoration of estuary habitat.

  12. Early feasibility testing and engineering development of a sutureless beating heart connector for left ventricular assist devices.

    PubMed

    Koenig, Steven C; Jimenez, Jorge H; West, Seth D; Sobieski, Michael A; Choi, Young; Monreal, Gretel; Giridharan, Guruprasad A; Soucy, Kevin G; Slaughter, Mark S

    2014-01-01

    APK Advanced Medical Technologies (Atlanta, GA) is developing a sutureless beating heart (SBH) left ventricular assist device (LVAD) connector system consisting of anchoring titanium coil, titanium cannula with integrated silicone hemostatic valve, coring and delivery tool, and LVAD locking mechanism to facilitate LVAD inflow surgical procedures. Feasibility testing was completed in human cadavers (n = 4) under simulated normal and hypertensive conditions using saline to observe seal quality in degraded human tissue and assess anatomic fit; acutely in ischemic heart failure bovine model (n = 2) to investigate short-term performance and ease of use; and chronically for 30 days in healthy calves (n = 2) implanted with HeartWare HVAD to evaluate performance and biocompatibility. Complete hemostasis was achieved in human cadavers and animals at LV pressures up to 170 mm Hg. In animals, off-pump (no cardiopulmonary bypass) anchoring of the connector was accomplished in less than 1 minute with no residual bleeding after full delivery and locking of the LVAD; and implant of connector and LVAD were successfully completed in under 10 minutes with total procedure blood loss less than 100 ml. In chronic animals before necropsy, no signs of leakage or disruption at the attachment site were observed at systolic LV pressures >200 mm Hg. PMID:25238500

  13. Early feasibility testing and engineering development of the transapical approach for the HeartWare MVAD ventricular assist system.

    PubMed

    Tamez, Daniel; LaRose, Jeffrey A; Shambaugh, Charles; Chorpenning, Katherine; Soucy, Kevin G; Sobieski, Michael A; Sherwood, Leslie; Giridharan, Guruprasad A; Monreal, Gretel; Koenig, Steven C; Slaughter, Mark S

    2014-01-01

    Implantation of ventricular assist devices (VADs) for the treatment of end-stage heart failure (HF) falls decidedly short of clinical demand, which exceeds 100,000 HF patients per year. Ventricular assist device implantation often requires major surgical intervention with associated risk of adverse events and long recovery periods. To address these limitations, HeartWare, Inc. has developed a platform of miniature ventricular devices with progressively reduced surgical invasiveness and innovative patient peripherals. One surgical implant concept is a transapical version of the miniaturized left ventricular assist device (MVAD). The HeartWare MVAD Pump is a small, continuous-flow, full-support device that has a displacement volume of 22 ml. A new cannula configuration has been developed for transapical implantation, where the outflow cannula is positioned across the aortic valve. The two primary objectives for this feasibility study were to evaluate anatomic fit and surgical approach and efficacy of the transapical MVAD configuration. Anatomic fit and surgical approach were demonstrated using human cadavers (n = 4). Efficacy was demonstrated in acute (n = 2) and chronic (n = 1) bovine model experiments and assessed by improvements in hemodynamics, biocompatibility, flow dynamics, and histopathology. Potential advantages of the MVAD Pump include flow support in the same direction as the native ventricle, elimination of cardiopulmonary bypass, and minimally invasive implantation. PMID:24399057

  14. Early Feasibility Testing and Engineering Development of the Transapical Approach for the HeartWare MVAD Ventricular Assist System

    PubMed Central

    Tamez, Daniel; LaRose, Jeffrey A.; Shambaugh, Charles; Chorpenning, Katherine; Soucy, Kevin G; Sobieski, Michael A; Sherwood, Leslie; Giridharan, Guruprasad A; Monreal, Gretel; Koenig, Steven C; Slaughter, Mark S

    2014-01-01

    Implantation of ventricular assist devices (VADs) for treatment of end-stage heart failure (HF) falls decidedly short of clinical demand, which exceeds 100,000 HF patients per year. VAD implantation often requires major surgical intervention with associated risk of adverse events and long recovery periods. To address these limitations, HeartWare, Inc. (Miami Lakes, FL) has developed a platform of miniature ventricular devices with progressively reduced surgical invasiveness and innovative patient peripherals. One surgical implant concept is a transapical version of the miniaturized left ventricular assist device (MVAD). The HeartWare MVAD Pump® is a small, continuous flow, full-support device that has a displacement volume of 22mL. A new cannula configuration has been developed for transapical implantation, where the outflow cannula is positioned across the aortic valve. The two primary objectives for this feasibility study were to evaluate anatomic fit and surgical approach and efficacy of the transapical MVAD configuration. Anatomic fit and surgical approach were demonstrated using human cadavers (n=4). Efficacy was demonstrated in acute (n =2) and chronic (n = 1) bovine model experiments and assessed by improvements in hemodynamics, biocompatibility, flow dynamics, and histopathology. Potential advantages of the MVAD Pump include flow support in the same direction as the native ventricle, elimination of cardiopulmonary bypass, and minimally-invasive implantation. PMID:24399057

  15. Estuaries: Where Rivers Meet the Sea

    NSDL National Science Digital Library

    Take your students on an EstuaryLive telecast! EstuaryLive brings free, live internet field trips in four different estuaries around the country, right to your classroom. These online field trips are the next best thing to an actual trip to an estuary, providing students with an exciting and new way to learn about unique estuarine ecosystems. The site also includes archived webcasts and teacher resources including classroom activities and a glossary.

  16. Stream, lake, estuary, and ocean pollution, 2nd edition

    SciTech Connect

    Nemerow, N.L. (ed.)

    1991-01-01

    This book, an updated version of the 1985 edition, contains thirteen chapters, beginning with a preface which provides the objective of the book. The primary objective is to offer a comprehensive survey of the biological, hydrological, mathematical, and biochemical aspects of stream, lake, estuary, and ocean pollution analysis. The book also contains ten appendices of useful tables and nomographs of pertinent data. This book provides a very good summary and review of stream, lake, estuary, and ocean pollution. This book is recommended for environmental engineering students, environmental consulting engineers, and regulatory personnel. It provides an excellent summary of the field of stream and lake analysis and modeling. Every chapter includes a significant number of questions and pertinent references.

  17. MACROINVERTEBRATE PROTOCOLS ON ESTUARIES IN NEW JERSEY

    EPA Science Inventory

    Estuaries of the Atlantic coastal New Jersey extend from Newark Bay southward to Cape May Inlet. The rich diversities of habitats found in these estuaries provide important nursery areas for fish and marine invertebrates. Federal and state agencies routinely monitor estuaries fo...

  18. Ecology of estuaries: Anthropogenic effects

    SciTech Connect

    Kennish, M.J.

    1992-01-01

    Estuaries and near-shore oceanic water are subjected to a multitude of human wastes. The principal objective of this book is to examine anthropogenic effects on estuaries, and it focuses primarily on contaminants in coastal systems. Covered within various chapters are the following topics: waste disposal strategies; definition and classification of pollutants (including organic loading, oil pollution, polynuclear aromatic hydrocarbons; chlorinated hydrocarbons; heavy metals; radionuclides) biological impacts; waste management; impacts of power plants; dredging and spoil disposal; case studies, primarily Chesapeake Bay. The book serves as a text and as a reference.

  19. The Modification of an Estuary

    NASA Astrophysics Data System (ADS)

    Nichols, Frederic H.; Cloern, James E.; Luoma, Samuel N.; Peterson, David H.

    1986-02-01

    The San Francisco Bay estuary has been rapidly modified by human activity. Diking and filling of most of its wetlands have eliminated habitats for fish and waterfowl; the introduction of exotic species has transformed the composition of its aquatic communities; reduction of freshwater inflow by more than half has changed the dynamics of its plant and animal communities; and wastes have contaminated its sediments and organisms. Continued disposal of toxic wastes, the probable further reduction in freshwater inflow, and the possible synergy between the two provide the potential for further alteration of the estuary's water quality and biotic communities.

  20. DELAWARE ESTUARY A MANAGEMENT PLAN FOR THE DELAWARE ESTUARY

    EPA Science Inventory

    Wise conservation and management of the Delaware Estuary is arguably the most important cooperative environmental initiative ever jointly undertaken by the States of New Jersey, Pennsylvania, and Delaware. While much has been accomplished over the past few decades to improve wate...

  1. Facilitation of the Estuary/Ocean Subgroup for Federal Research, Monitoring, and Evaluation, FY08 Annual Report

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L.

    2008-09-29

    The Estuary/Ocean Subgroup (EOS) is part of the research, monitoring, and evaluation (RME) effort that the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) developed in response to obligations arising from the Endangered Species Act as applied to operation of the Federal Columbia River Power System (FCRPS). The goal of the EOS project is to facilitate activities of the estuary/ocean RME subgroup as it coordinates design and implementation of federal RME in the lower Columbia River and estuary. In fiscal year 2008 (FY08), EOS project accomplishments included 1) subgroup meetings; 2) participation in the estuary work group of the Pacific Northwest Aquatic Monitoring Partnership; 3) project management via the project tracking system, Pisces; 4) quarterly project status reports; and 5) a major revision to the Estuary RME document and its subsequent regional release (new version January 2008). Many of the estuary RME recommendations in this document were incorporated into the Biological Opinion on hydrosystem operations (May 2008). In summary, the FY08 EOS project resulted in expanded, substantive coordination with other regional RME forums, a new version of the federal Estuary RME program document, and implementation coordination. This annual report is a FY08 deliverable for the project titled Facilitation of the Estuary/Ocean Subgroup.

  2. Facilitation of the Estuary/Ocean Subgroup for Federal Research, Monitoring and Evaluation FY08 Annual Report.

    SciTech Connect

    Johnson, GE; Diefenderfer, HL [Pacific Northwest National Laboratory

    2008-09-29

    The Estuary/Ocean Subgroup (EOS) is part of the research, monitoring, and evaluation (RME) effort that the Action Agencies (Bonneville Power Administration (BPA), U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) developed in response to obligations arising from the Endangered Species Act as applied to operation of the Federal Columbia River Power System (FCRPS). The goal of the EOS project is to facilitate activities of the estuary/ocean RME subgroup as it coordinates design and implementation of federal RME in the lower Columbia River and estuary. In fiscal year 2008 (FY08), EOS project accomplishments included (1) subgroup meetings; (2) participation in the estuary work group of the Pacific Northwest Aquatic Monitoring Partnership; (3) project management via BPA's project tracking system, Pisces; (4) quarterly project status reports; and (5) a major revision to the Estuary RME document and its subsequent regional release (new version January 2008). Many of the estuary RME recommendations in this document were incorporated into the Biological Opinion on FCRPS operations (May 2008). In summary, the FY08 EOS project resulted in expanded, substantive coordination with other regional RME forums, a new version of the federal Estuary RME program document, and implementation coordination. This annual report is a FY08 deliverable for the project titled Facilitation of the Estuary/Ocean Subgroup.

  3. Historic Habitat Opportunities and Food-Web Linkages of Juvenile Salmon in the Columbia River Estuary, Annual Report of Research.

    SciTech Connect

    Bottom, Daniel L.; Simenstad, Charles A.; Campbell, Lance [Northwest Fisheries Science Center

    2009-05-15

    In 2002 with support from the U.S. Army Corps of Engineers (USACE), an interagency research team began investigating salmon life histories and habitat use in the lower Columbia River estuary to fill significant data gaps about the estuary's potential role in salmon decline and recovery . The Bonneville Power Administration (BPA) provided additional funding in 2004 to reconstruct historical changes in estuarine habitat opportunities and food web linkages of Columbia River salmon (Onchorhynchus spp.). Together these studies constitute the estuary's first comprehensive investigation of shallow-water habitats, including selected emergent, forested, and scrub-shrub wetlands. Among other findings, this research documented the importance of wetlands as nursery areas for juvenile salmon; quantified historical changes in the amounts and distributions of diverse habitat types in the lower estuary; documented estuarine residence times, ranging from weeks to months for many juvenile Chinook salmon (O. tshawytscha); and provided new evidence that contemporary salmonid food webs are supported disproportionately by wetland-derived prey resources. The results of these lower-estuary investigations also raised many new questions about habitat functions, historical habitat distributions, and salmon life histories in other areas of the Columbia River estuary that have not been adequately investigated. For example, quantitative estimates of historical habitat changes are available only for the lower 75 km of the estuary, although tidal influence extends 217 km upriver to Bonneville Dam. Because the otolith techniques used to reconstruct salmon life histories rely on detection of a chemical signature (strontium) for salt water, the estuarine residency information we have collected to date applies only to the lower 30 or 35 km of the estuary, where fish first encounter ocean water. We lack information about salmon habitat use, life histories, and growth within the long tidal-fresh reaches of the main-stem river and many tidally-influenced estuary tributaries. Finally, our surveys to date characterize wetland habitats within island complexes distributed in the main channel of the lower estuary. Yet some of the most significant wetland losses have occurred along the estuary's periphery, including shoreline areas and tributary junctions. These habitats may or may not function similarly as the island complexes that we have surveyed to date. In 2007 we initiated a second phase of the BPA estuary study (Phase II) to address specific uncertainties about salmon in tidal-fresh and tributary habitats of the Columbia River estuary. This report summarizes 2007 and 2008 Phase II results and addresses three principal research questions: (1) What was the historic distribution of estuarine and floodplain habitats from Astoria to Bonneville Dam? (2) Do individual patterns of estuarine residency and growth of juvenile Chinook salmon vary among wetland habitat types along the estuarine tidal gradient? (3) Are salmon rearing opportunities and life histories in the restoring wetland landscape of lower Grays River similar to those documented for island complexes of the main-stem estuary? Phase II extended our analysis of historical habitat distribution in the estuary above Rkm 75 to near Bonneville Dam. For this analysis we digitized the original nineteenth-century topographic (T-sheets) and hydrographic (H-sheets) survey maps for the entire estuary. Although all T-sheets (Rkm 0 to Rkm 206) were converted to GIS in 2005 with support for the USACE estuary project, final reconstruction of historical habitats throughout the estuary requires completion of the remaining H-sheet GIS maps above Rkm 75 and their integration with the T-sheets. This report summarizes progress to date on compiling the upper estuary H-sheets above Rkm 75. For the USACE estuary project, we analyzed otoliths from Chinook salmon collected near the estuary mouth in 2003-05 to estimate variability in estuary residence times among juvenile out migrants. In Phase II we expanded these analyses to comp

  4. SAN FRANCISCO ESTUARY INSTITUTE CONTRIBUTION

    E-print Network

    Quality Impacts Due to Dredging and Disposal on Sensitive Fish Species in San Francisco Bay Prepared Figure 3-1. Chemical processes upon resuspension caused by dredging. ...............................................................19 Figure 3-2. Location of sediment sampling at San Francisco Estuary dredging projects (1993 ­ 2003

  5. The Value of Healthy Estuaries

    NSDL National Science Digital Library

    Robert Christian (Thomas Harriot College of Arts and Sciences; )

    2009-03-22

    Healthy estuaries are critical to humans and wildlife. They provide food, supporting both commercial and recreational fisheries, treat waste and runoff to maintain water quality, protect coastal areas from natural hazards, connect bodies of water for transportation and marine operations, and nurture a balance of the food web upon which all life depends.

  6. Technical and Engineering Feasibility Study of the Vitrification of Plutonium-Bearing Sludges at the Krasnoyarsk Mining and Chemical Combine by Means of Microwave Heating

    SciTech Connect

    Revenko, Y.A.; Kudinov, K.G.; Tretyakov, A.A.; Vassilyev, A.V.; Borisov, G.B.; Nazarov, A.V.; Aloy, A.S.; Shvedov, A.A.; Gusakov, B.V.; Jardine, L.J.

    2000-03-03

    This engineering feasibility study compared three possible technical options and their economic viability of processing plutonium-bearing sludges containing 0.6 MT of weapons-grade Pu accumulated at the Mining and Chemical Combine (MCC) at Krasnoyarsk. In Option 1, the baseline, the sludges are processed by extraction and purification of plutonium for storage using existing technologies, and the non-soluble radioactive residues generated in these processes undergo subsequent solidification by cementation. Options 2 and 3 involve the direct immobilization of plutonium-bearing sludges into a solid matrix (without any Pu extraction) using a microwave solidification process in a metal crucible to produce a glass, which is boron-silicate in Option 2 and phosphate glass in Option 3. In all three options, the solid radioactive waste end products will be placed in storage for eventual geologic disposal. Immobilization of residual plutonium into glass-like matrices provides both safer storage over the lifetime of the radionuclides and greater security against unauthorized access to stored materials than does the extraction and concentration of PuO{sub 2}, supporting our efforts toward non-proliferation of fissile materials. Although immobilization in boron-silicate glass appears now to be marginally preferable compared to the phosphate glass option, a number of technical issues remain to be assessed by further study to determine the preferable immobilization option.

  7. Carbon dioxide emissions from Indian monsoonal estuaries

    NASA Astrophysics Data System (ADS)

    Sarma, V. V. S. S.; Viswanadham, R.; Rao, G. D.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Kumar, N. A.; Rao, D. B.; Sridevi, T.; Krishna, M. S.; Reddy, N. P. C.; Sadhuram, Y.; Murty, T. V. R.

    2012-02-01

    Estuaries are known to be strong source for atmospheric CO2, however, little information is available from Indian estuaries. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge (wet) period. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ˜300 and 18492 ?atm which are within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

  8. The Need for Definitions in Understanding Estuaries

    NASA Astrophysics Data System (ADS)

    Elliott, M.; McLusky, D. S.

    2002-12-01

    This paper considers what the definition/classification of estuaries has taught us and why there is a need for classification systems. It further considers why we need to define an estuary and its constituent parts, including the fundamental difficulty and dilemma of trying to define parts of a continuum, as a means to both understanding and managing that estuary. The review considers where an estuary starts and ends and the relative merits of defining estuaries in terms of their biology, physics, chemistry, geographic nature and socio-economic units. It briefly discusses the need for legal and planning definitions and the linkages between science and management. Following this, we present a generic framework for the definition, classification, monitoring, assessment, reporting and management of estuaries. In particular, it is argued that scientists should engage in the debate on the definition of estuaries for legal and socio-economic purposes. It is concluded here that as existing definitions will never be suitable for all needs, a different approach is required. The proposed ' Expert Judgement Checklist Approach ' could provide guidance for those needing to define/delimit an estuary while still acknowledging the inherent variability of such systems. The proposed system mostly relates to the European, temperate estuary, but there are lessons here for estuaries worldwide.

  9. 75 FR 34975 - Notice of Estuary Habitat Restoration Council's Intent to Revise its Estuary Habitat Restoration...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-21

    ...Policy task force goals and in identifying focus areas for the estuary habitat restoration strategy, such as: climate adaptation restoration, socio-economic benefits of estuary habitat restoration, and geographic restoration...

  10. NTRE extended life feasibility assessment

    NASA Astrophysics Data System (ADS)

    Results of a feasibility analysis of a long life, reusable nuclear thermal rocket engine are presented in text and graph form. Two engine/reactor concepts are addressed: the Particle Bed Reactor (PBR) design and the Commonwealth of Independent States (CIS) concept. Engine design, integration, reliability, and safety are addressed by various members of the NTRE team from Aerojet Propulsion Division, Energopool (Russia), and Babcock & Wilcox.

  11. NTRE extended life feasibility assessment

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Results of a feasibility analysis of a long life, reusable nuclear thermal rocket engine are presented in text and graph form. Two engine/reactor concepts are addressed: the Particle Bed Reactor (PBR) design and the Commonwealth of Independent States (CIS) concept. Engine design, integration, reliability, and safety are addressed by various members of the NTRE team from Aerojet Propulsion Division, Energopool (Russia), and Babcock & Wilcox.

  12. MAPPING BATHYMETRY AND BOTTOM TYPE IN A SHALLOW ESTUARY

    EPA Science Inventory

    Bathymetry and bottom type are important in characterizing estuaries and their ecology but hard to map, especially in shallow estuaries. Acoustic backscattering was used to remotely sense these properties in the shallow Slocums River Estuary of Massachusetts. Acoustic pulses were...

  13. Comparison of Nutrient Drivers and Response Metrics in Oregon Estuaries

    EPA Science Inventory

    With the goal of assessing sensitivity to nutrient enrichment, we present a cross-estuary comparison of nutrient sources, levels, and biological responses (phytoplankton and macroalgae) for thirteen Oregon estuaries. Nitrogen levels in the upstream portions of the estuaries are ...

  14. Tidal wetland conservation and restoration for flood mitigation in estuaries and deltas: examples and global potential

    NASA Astrophysics Data System (ADS)

    Temmerman, Stijn; Smolders, Sven; Stark, Jeroen; meire, patrick

    2014-05-01

    Low-lying and densely populated deltas and estuaries are world widely exposed to flood risks caused by storm surges. On the one hand, global change is increasing these flood risks through accelerating sea level rise and increasing storm intensity, but on the other hand, local-scale human impacts on deltas and estuaries are in many cases even more increasing the vulnerability to floods. Here we address the degradation and reclamation of tidal wetlands (i.e. salt marshes in the temperate zone and mangroves in the tropical zone) as a major source for increasing vulnerability to flooding of estuaries and deltas. Firstly, we present examples of flood mitigation by tidal wetland conservation and restoration, and secondly we explore the potentials and limitations for global application of this approach of ecosystem-based flood defense (see Temmerman et al. 2013). First, we use the Scheldt estuary (SW Netherlands and Belgium) as an example where historic wetland reclamation has importantly contributed to increasing flood risks, and where tidal marsh restoration on the previously reclaimed land is nowadays brought into large-scale practice as an essential part of the flood defense system. Based on data and hydrodynamic modelling, we show that large-scale historic marsh reclamation has largely reduced the water storage capacity of the estuary and has reduced the friction to propagating flood waves, resulting in an important landward increase of tidal and storm surge levels. Hydrodynamic model scenarios demonstrate how tidal and storm surge propagation through the estuary are affected by tidal marsh properties, including the surface area, elevation, vegetation and position of marshes along the estuary. We show that nowadays tidal wetland creation on previously reclaimed land is applied as an essential part of the flood defense system along the Scheldt estuary. Secondly, a global analysis is presented of the potential application of tidal wetlands in flood mitigation in estuaries and deltas worldwide. We discuss the societal benefits and drawbacks of wetland creation for flood defense, and provide an estimation of where on Earth this approach could be feasible. This shows that many of the largest urban populations that are at risk from coastal flooding, are located in large deltas and estuaries, such as in Southeast Asia, North America and Europe. We argue that many of these vulnerable areas are potentially well suited to include wetland conservation and restoration as an essential part of adaptation and mitigation strategies against storm surge flood risks. References: Temmerman S., Meire P., Bouma T.J., Herman P.M.J., Ysebaert T., De Vriend H.J. (2013) Ecosystem-based coastal defense in the face of global change. Nature, 504, P. 79-83, doi:10.1038/nature12859.

  15. What are the costs and benefits of biodiversity recovery in a highly polluted estuary?

    PubMed

    Pascual, M; Borja, A; Franco, J; Burdon, D; Atkins, J P; Elliott, M

    2012-01-01

    Biodiversity recovery measures have often been ignored when dealing with the restoration of degraded aquatic systems. Furthermore, biological valuation methods have been applied only spatially in previous studies, and not jointly on a temporal and spatial scale. The intense monitoring efforts carried out in a highly polluted estuary, in northern Spain (Nervión estuary), allowed for the economic valuation of the costs and the biological valuation of the benefits associated with a 21 years sewage scheme application. The analysis show that the total amount of money invested into the sewage scheme has contributed to the estuary's improvement of both environmental and biological features, as well as to an increase in the uses and services provided by the estuary. However, the inner and outer parts of the estuary showed different responses. An understanding of the costs and trajectories of the environmental recovery of degraded aquatic systems is increasingly necessary to allow policy makers and regulators to formulate robust, cost-efficient and feasible management decisions. PMID:22088272

  16. DENSITY-DEPENDENT IMPACTS OF BIOIRRIGATION BY THE BURROWING SHRIMP UPOGEBIA PUGETTENSIS ON BENTHIC FLUXES AND POREWATER SOLUTE DISTRIBUTIONS IN PACIFIC NORTHWEST ESTUARIES

    EPA Science Inventory

    Burrowing thalassinid shrimp are major ecosystem engineering species of Pacific estuaries and can structure the physical, chemical, and biotic properties of sediments. Feeding and burrow irrigation by benthic organisms can increase the remineralization rates of organic material (...

  17. SSPA Equipment Engineering Feasibility Report

    SciTech Connect

    N.E. Woolstenhulme; C.R. Clark

    2011-09-01

    In response to a demanding reactor conversion schedule, construction of the Shielded Sample Preparation Area (SSPA) was initiated in 2010 to augment the existing capabilities of the Hot Fuel Examination Facility (HFEF). While HFEF is and will remain the workhorse for post irradiation sample preparation, there is currently a large backlog of Post-Irradiation Examination (PIE) experiments caused by numerous competing projects (this backlog is expected to continue for the foreseeable future). HFEF, in its present configuration also lacks the ability to prepare samples suitable for several of the tests that have been identified for the successful conclusion of the RERTR program; these samples require fine detail machining of irradiated fuel plates.

  18. Morphodynamic equilibrium of alluvial estuaries

    NASA Astrophysics Data System (ADS)

    Tambroni, Nicoletta; Bolla Pittaluga, Michele; Canestrelli, Alberto; Lanzoni, Stefano; Seminara, Giovanni

    2014-05-01

    The evolution of the longitudinal bed profile of an estuary, with given plan-form configuration, subject to given tidal forcing at the mouth and prescribed values of water and sediment supply from the river is investigated numerically. Our main goal is to ascertain whether, starting from some initial condition, the bed evolution tends to reach a unique equilibrium configuration asymptotically in time. Also, we investigate the morphological response of an alluvial estuary to changes in the tidal range and hydrologic forcing (flow and sediment supply). Finally, the solution helps characterizing the transition between the fluvially dominated region and the tidally dominated region of the estuary. All these issues play an important role also in interpreting how the facies changes along the estuary, thus helping to make correct paleo-environmental and sequence-stratigraphic interpretations of sedimentary successions (Dalrymple and Choi, 2007). Results show that the model is able to describe a wide class of settings ranging from tidally dominated estuaries to fluvially dominated estuaries. In the latter case, the solution is found to compare satisfactory with the analytical asymptotic solution recently derived by Seminara et al. (2012), under the hypothesis of fairly 'small' tidal oscillations. Simulations indicate that the system always moves toward an equilibrium configuration in which the net sediment flux in a tidal cycle is constant throughout the estuary and equal to the constant sediment flux discharged from the river. For constant width, the bed equilibrium profile of the estuarine channel is characterized by two distinct regions: a steeper reach seaward, dominated by the tide, and a less steep upstream reach, dominated by the river and characterized by the undisturbed bed slope. Although the latter reach, at equilibrium, is not directly affected by the tidal wave, however starting from an initial uniform stream with the constant 'fluvial' slope, the final equilibrium state is reached through an erosional wave, which leads to bed degradation of the upstream 'fluvial reach'. For a given river discharge, the length of the tidal reach increases quite rapidly with tidal amplitude, up to some threshold value of the tidal amplitude above which the length of the estuary becomes comparable with the length of the tidal wave. When the channel plan-form is convergent, deposition of sediments of fluvial origin in the funnel-shaped region drastically changes the equilibrium configuration. The effect of an increasing channel convergence is thus to induce bed aggradation close to the inlet. Nevertheless, tidal forcing only slightly changes the non-tidal profile. The effect of increasing tidal oscillations again leads to an increase of the bed slope at the inlet and to a general bed degradation upstream. The effects of varying sediment supply, flow discharge and river width in the upstream reach have also been investigated and play an important role. Further geomorphological implications of these results will be discussed at the meeting. References Dalrymple, R. W., and K. Choi (2007), Morphologic and facies trends through the fluvialmarine transition in tide-dominated depositional systems: A schematic framework for environmental and sequence-stratigraphic interpretation, Earth-Science Reviews, 81(3-4), 135-174, doi:10.1016/j.earscirev.2006.10.002. Seminara, G., M. Bolla Pittaluga, and N. Tambroni (2012), Morphodynamic equilibrium of tidal channels, Environmental Fluid Mechanics: Memorial Volume in Honour of Prof. Gerhard H. Jirka, 153-174

  19. Carbon dioxide emissions from Indian monsoonal estuaries

    NASA Astrophysics Data System (ADS)

    Sarma Vedula, VSS

    2012-07-01

    The oceans act as a net sink for atmospheric CO2, however, the role of coastal bodies on global CO2 fluxes remains unclear due to lack of data. The estimated absorption of CO2 from the continental shelves, with limited data, is 0.22 to 1.0 PgC/y, and of CO2 emission by estuaries to the atmosphere is 0.27 PgC/y. The estimates from the estuaries suffer from large uncertainties due to large variability and lack of systematic data collection. It is especially true for Southeast Asian estuaries as the biogeochemical cycling of material are different due to high atmospheric temperature, seasonality driven by monsoons, seasonal discharge etc. In order to quantify CO2 emissions from the Indian estuaries, samples were collected at 27 estuaries all along the Indian coast during discharge wet and dry periods. The emissions of CO2 to the atmosphere from Indian estuaries were 4-5 times higher during wet than dry period. The pCO2 ranged between ~300 and 18492 microatm which were within the range of world estuaries. The mean pCO2 and particulate organic carbon (POC) showed positive relation with rate of discharge suggesting availability of high quantities of organic matter that led to enhanced microbial decomposition. The annual CO2 fluxes from the Indian estuaries, together with dry period data available in the literature, amounts to 1.92 TgC which is >10 times less than that from the European estuaries. The low CO2 fluxes from the Indian estuaries are attributed to low flushing rates and less human settlements along the banks of the Indian estuaries.

  20. Country-wide assessment of estuary health: An approach for integrating pressures and ecosystem response in a data limited environment

    NASA Astrophysics Data System (ADS)

    Van Niekerk, L.; Adams, J. B.; Bate, G. C.; Forbes, A. T.; Forbes, N. T.; Huizinga, P.; Lamberth, S. J.; MacKay, C. F.; Petersen, C.; Taljaard, S.; Weerts, S. P.; Whitfield, A. K.; Wooldridge, T. H.

    2013-09-01

    Population and development pressures increase the need for proactive strategic management on a regional or country-wide scale - reactively protecting ecosystems on an estuary-by-estuary basis against multiple pressures is 'resource hungry' and not feasible. Proactive management requires a strategic assessment of health so that the most suitable return on investment can be made. A country-wide assessment of the nearly 300 functional South African estuaries examined both key pressures (freshwater inflow modification, water quality, artificial breaching of temporarily open/closed systems, habitat modification and exploitation of living resources) and health state. The method used to assess the type and level of the different pressures, as well as the ecological health status of a large number of estuaries in a data limited environment is described in this paper. Key pressures and the ecological condition of estuaries on a national scale are summarised. The template may also be used to provide guidance to coastal researchers attempting to inform management in other developing countries. The assessment was primarily aimed at decision makers both inside and outside the biodiversity sector. A key starting point was to delineate spatially the estuary functional zone (area) for every system. In addition, available data on pressures impacting estuaries on a national scale were collated. A desktop national health assessment, based on an Estuarine Health Index developed for South African ecological water requirement studies, was then applied systematically. National experts, all familiar with the index evaluated the estuaries in their region. Individual estuarine health assessment scores were then translated into health categories that reflect the overall status of South Africa's estuaries. The results showed that estuaries in the warm-temperate biogeographical zone are healthier than those in the cool-temperate and subtropical zones, largely reflecting the country's demographics and developmental pressures. A major finding was that, while a large number of South Africa's estuaries are still in an excellent to good condition, they tend to represent very small systems (<150 ha in size) in rural areas with few pressures. Larger systems, which are more important as nursery grounds because of their size, and also of higher economic and ecological importance, are in a fair to poor condition. This was due to pressures within the catchments influencing these downstream systems, and degradation as a result of direct development within the estuary functional zone.

  1. A Mathematical and Numerical Model for the Transport of Salinity in High Environmental Value Estuaries

    Microsoft Academic Search

    M. Casteleiro; I. Colominas; F. Navarrina

    In this paper, a numerical model for the simulation of the hydrodynamic and of the evolution of the salinity in shallow water estuaries is presented. This tool is intended to predict the possible eects of Civil Engineering public works and other human actions (dredging, building of docks, spillings, etc.) on the marine habitat, and to evaluate their environmental impact in

  2. Protocols for Monitoring Habitat Restoration Projects in the Lower Columbia River and Estuary

    SciTech Connect

    Roegner, G. Curtis; Diefenderfer, Heida L.; Borde, Amy B.; Thom, Ronald M.; Dawley, Earl M.; Whiting, Allan H.; Zimmerman, Shon A.; Johnson, Gary E.

    2008-04-25

    Protocols for monitoring salmon habitat restoration projects are essential for the U.S. Army Corps of Engineers' environmental efforts in the Columbia River estuary. This manual provides state-of-the science data collection and analysis methods for landscape features, water quality, and fish species composition, among others.

  3. A Climate Ready Estuaries Vulnerability Assessment

    EPA Science Inventory

    The purpose of the the Climate Ready Estuaries program is to build capacity in the National Estuary Programs (NEPs) for local leadership and expertise to adapt to the effects of climate change through a joint effort with the NEPs and EPA. Background The Climate Ready...

  4. NEW HAMPSHIRE ESTUARIES PROJECT MANAGEMENT PLAN

    EPA Science Inventory

    This Comprehensive Conservation and Management Plan of the New Hampshire Estuaries Project presents a broad framework and specific list of actions to protect and enhance the environmental quality of the estuaries of the State of New Hampshire. It is intended to be a guide for all...

  5. NEW HAMPSHIRE ESTUARIES PROJECT MANAGEMENT PLAN, 2000

    EPA Science Inventory

    The Comprehensive Conservation and Management Plan of the New Hampshire Estuaries Project presents a broad framework and specific list of actions to protect and enhance the environmental quality of the estuaries of the State of New Hampshire. It is intended to be a guide for all ...

  6. Feasibility study of an Integrated Program for Aerospace-vehicle Design (IPAD) system. Volume 3: Engineering creative/evaluation processes, phase 1, task 2

    NASA Technical Reports Server (NTRS)

    Garrocq, C. A.; Hosek, J. J.

    1973-01-01

    A series of functional flow charts are considered that were developed to properly identify and record the degree of participation of the disciplines considered in this feasibility study and the type of data required in the design process.

  7. Facilitation of the Estuary/Ocean Subgroup for Federal Research, Monitoring, and Evaluation, FY10 Annual Report

    SciTech Connect

    Johnson, Gary E.

    2010-10-26

    The Estuary/Ocean Subgroup (EOS) is part of the research, monitoring, and evaluation (RME) effort that the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) developed in response to obligations arising from the Endangered Species Act as applied to operation of the Federal Columbia River Power System (FCRPS). The goal of the EOS project is to facilitate activities of the estuary/ocean RME subgroup as it coordinates design and implementation of federal RME in the lower Columbia River and estuary. The EOS is one of multiple work groups in the federal research, monitoring, and evaluation (RME) effort developed in response to responsibilities arising from the Endangered Species Act as a result of operation of the FCRPS. The EOS is tasked by NOAA Fisheries and the Action Agencies to design and coordinate implementation of the federal RME plan for the lower Columbia River and estuary, including the plume.

  8. Turbidity and sediment transport in a muddy sub-estuary

    Microsoft Academic Search

    R. J. Uncles; J. A. Stephens

    2010-01-01

    Sub-estuaries, i.e. tidal creeks and also larger estuaries that branch off the stem of their main estuary, are commonplace in many estuarine systems. Their physical behaviour is affected not only by tributary inflows, winds and tides, but also by the properties and behaviour of their main estuary. Measurements extending over more than an annual cycle are presented for the Tavy

  9. Dissolved oxygen in two Oregon estuaries: The importance of the ocean-estuary connection - May 16, 2011

    EPA Science Inventory

    We examined the role of the ocean ?estuary connection in influencing periodic reductions in dissolved oxygen (DO) levels in Yaquina and Yachats estuaries, Oregon, USA. In the Yaquina Estuary, there is close coupling between the coastal ocean and the estuary. As a result, low DO ...

  10. D-21B RBCC Modification Feasibility Study

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This report presents a feasibility study on the modifications required to re-engine the Lockheed D-21 Drone for use as a NASA RBCC engine. An introduction, background information, engine configuration and performance, propulsion system integration, loads/thermal analysis, avionics/systems, flight test results, costs and work schedule, and some conclusions are presented.

  11. Facilitation of the Estuary/Ocean Subgroup for Research, Monitoring and Evaluation - FY07 Annual Report.

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L. [Pacific Northwest National Laboratory

    2007-10-10

    This annual report is a deliverable for fiscal year 2007 (FY07) for Project 2002-077-00, Facilitation of the Estuary/Ocean Subgroup (EOS). The EOS is part of the research, monitoring, and evaluation (RME) effort of the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) developed in response to responsibilities arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The goal of the EOS project is to facilitate activities of the estuary/ocean RME subgroup as it coordinates design and implementation of federal RME in the lower Columbia River and estuary. In FY07, EOS project accomplishments included (1) subgroup meetings; (2) participation in the estuary work group of the Pacific Northwest Aquatic Monitoring Partnership; (3) project management via the project tracking system, PISCES; (4) quarterly project status reports; and (5) a major revision to the Estuary RME Plan (new version September 2007) based on comments by EOS members and invited reviewers.

  12. Facilitation of the Estuary/Ocean Subgroup for Research, Monitoring, and Evaluation, FY07 Annual Report

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L.

    2007-10-10

    This annual report is a deliverable for fiscal year 2007 (FY07) for Project 2002-077-00, Facilitation of the Estuary/Ocean Subgroup (EOS). The EOS is part of the research, monitoring, and evaluation (RME) effort the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) developed in response to responsibilities arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The goal of the EOS project is to facilitate activities of the estuary/ocean RME subgroup as it coordinates design and implementation of federal RME in the lower Columbia River and estuary. In FY07, EOS project accomplishments included 1) subgroup meetings; 2) participation in the estuary work group of the Pacific Northwest Aquatic Monitoring Partnership; 3) project management via the project tracking system, PISCES; 4) quarterly project status reports; and 5) a major revision to the Estuary RME Plan (new version September 2007) based on comments by EOS members and invited reviewers.

  13. Major hydrogeochemical processes in an Acid Mine Drainage affected estuary.

    PubMed

    Asta, Maria P; Calleja, Maria Ll; Pérez-López, Rafael; Auqué, Luis F

    2015-02-15

    This study provides geochemical data with the aim of identifying and quantifying the main processes occurring in an Acid Mine Drainage (AMD) affected estuary. With that purpose, water samples of the Huelva estuary were collected during a tidal half-cycle and ion-ion plots and geochemical modeling were performed to obtain a general conceptual model. Modeling results indicated that the main processes responsible for the hydrochemical evolution of the waters are: (i) the mixing of acid fluvial water with alkaline ocean water; (ii) precipitation of Fe oxyhydroxysulfates (schwertmannite) and hydroxides (ferrihydrite); (iii) precipitation of Al hydroxysulfates (jurbanite) and hydroxides (amorphous Al(OH)3); (iv) dissolution of calcite; and (v) dissolution of gypsum. All these processes, thermodynamically feasible in the light of their calculated saturation states, were quantified by mass-balance calculations and validated by reaction-path calculations. In addition, sorption processes were deduced by the non-conservative behavior of some elements (e.g., Cu and Zn). PMID:25530015

  14. US Environmental Protection Agency: National Estuary Program

    NSDL National Science Digital Library

    Established in 1987 by amendments to the Clean Water Act and administered by the Environmental Protection Agency's Office of Wetlands, Oceans, and Watersheds (OWOW), the National Estuary Program (NEP) identifies, restores and protects estuaries along the coasts of the United States. Unlike the traditional regulatory approaches to environmental protection, the NEP targets a wide range of issues and engages local communities in the process. At the site users can find descriptions of the NEP, specific NEP projects, estuaries involved in the NEP (including location, size, presence of threatened and endangered species, major habitat types, etc.), a current awareness section, links to related sites, and the full text of NEP's newsletter, Coastlines.

  15. The Substation of the Future: A Feasibility Study

    E-print Network

    The Substation of the Future: A Feasibility Study Final Project Report Power Systems Engineering Research Center Empowering Minds to Engineer the Future Electric Energy System #12;Substation of the Future Engineering Research Center (PSERC) research project T-38 titled "Substation of the Future: A Feasibility

  16. Integer Feasibility of Random Polytopes Karthekeyan Chandrasekaran

    E-print Network

    Vempala, Santosh

    Integer Feasibility of Random Polytopes Karthekeyan Chandrasekaran School of Engineering Georgia Institute of Technology vempala@gatech.edu ABSTRACT We study the Chance-Constrained Integer is integer feasible with prob- ability at least 1 - . We consider the case when the en- tries

  17. Sault Tribe Wind Energy Feasibility Study

    SciTech Connect

    Toni Osterhout; Global Energy Concepts

    2005-07-31

    The Sault Tribe conducted a feasibility study on tribal lands in the Upper Peninsula of Michigan to determine the technical and economic feasibility of both small and large-scale wind power development on tribal lands. The study included a wind resource assessment, transmission system analysis, engineering and regulatory analyzes and assessments.

  18. Feasibility study of a 6V-92TA homogeneous auto-ignited two-stroke (HAT) compressed-natural-gas-engine. Topical report, August 1989May 1990

    Microsoft Academic Search

    R. M. Kakwani; R. E. Winsor

    1990-01-01

    The objective of the project was to modify a two-stroke 6V-92TA diesel engine to operate on natural gas using a simple system with gas addition to the compressor inlet and a spark plug for cold start and non-autoignition engine operation. The engine was to be operated at most speed-load conditions by autoignition of the premixed gas-air mixture. This concept is

  19. Assessing the susceptibility of two UK estuaries to nutrient enrichment

    NASA Astrophysics Data System (ADS)

    Kadiri, Margaret; Bockelmann-Evans, Bettina; Rauen, William B.

    2014-10-01

    The susceptibility of two UK estuaries, the Severn and Solva Estuaries to the risks and impacts of nutrient enrichment was investigated in this study by examining nutrients, dissolved oxygen (DO) and turbidity concentrations in the estuaries and applying a risk assessment model based on the UK's Comprehensive Studies Task Team (CSTT) modelling approach. Both estuaries were found to be nutrient enriched. However, there was no evidence of oxygen depletion in the Severn and algal blooms were not observed due to high turbidity, strong tidal currents and tidally induced vertical mixing conditions in the estuary. Although algal blooms were observed in the Solva Estuary, the estuary was well-oxygenated due to the relatively high water exchange rate and consistent rapid flushing in the estuary. The conditions in the Solva Estuary were predicted to be favourable for phytoplankton productivity and the wider potential implications for future water quality protection strategies in the Solva were discussed.

  20. Alien reef-building polychaete drives long-term changes in invertebrate biomass and diversity in a small, urban estuary

    NASA Astrophysics Data System (ADS)

    McQuaid, K. A.; Griffiths, C. L.

    2014-02-01

    Two of the greatest threats to native biodiversity are the construction of artificial structures in natural environments and the introduction of invasive species. As the development and urbanisation of estuaries continues at an increasing rate worldwide, these environments are being simultaneously affected by these threats. This study quantifies the spread of an invasive reef-building polychaete, Ficopomatus enigmaticus, in a small, highly manipulated urban estuary in South Africa and investigates its role as an ecosystem engineer. Anthropogenic changes to the Zandvlei Estuary, including construction of a rubble weir and canalisation near the estuary mouth, construction of an extensive marina development and hardening of the banks with concrete, have facilitated the expansion of F. enigmaticus. The standing stock of F. enigmaticus increased from 13.69 t, as measured in 1986, to 50.03 t in 2012, due both to increase in the total area colonised and standing stock per m2. Since F. enigmaticus reefs support a greater biomass of infauna than adjacent sandy areas, total invertebrate biomass in the estuary is estimated to have increased from less than 0.30 t in 1942, to over 56.80 t in 2012, due mainly to hardening of banks in parts of the main estuary with concrete and construction of a marina system. A positive correlation between reef mass and infaunal biomass, density and diversity was also found.

  1. PECONIC ESTUARY PROGRAM TIDAL CREEK STUDY

    EPA Science Inventory

    EEA evaluated ten tidal creeks throughout the Peconic Estuary representing a wide range of watershed variables. Primary focus was directed towards the collection and analysis of the macrobenthic invertebrate communities of these ten tidal creeks. Analysis of the macrobenthic comm...

  2. EPA'S BENTHIC HABITAT DATA FOR YAQUINA ESTUARY

    EPA Science Inventory

    Scientists at EPA's National Health and Environmental Effects Research Laboratory, Western Ecology Division (WED) have been studying seafloor (benthic) habitats in Yaquina estuary for several years. Those studies were conducted as parts of several research projects, including: e...

  3. Copper speciation in estuaries and coastal waters

    E-print Network

    Kogut, Megan Brook, 1972-

    2002-01-01

    The goals of this dissertation are to better understand the sources and the Cu binding ability of ligands that control Cu toxicity in estuaries and harbors, where elevated Cu concentrations have caused documented toxic ...

  4. Estuaries and coastal waters need help

    Microsoft Academic Search

    Howard Levenson

    1987-01-01

    For years, our marine environments-estuaries, coastal waters, and the open ocean-have been used extensively by coastal communities and industries for the disposal of various wastes. Historically, marine waste disposal has been relatively cheap and has solved some short-term waste-management problems; however, its consequences include a general trend toward environmental degradation, particularly in estuaries and coastal waters. Thus, without protective measures,

  5. Estuaries.

    ERIC Educational Resources Information Center

    Awkerman, Gary L.

    This publication is designed for use in standard science curricula to develop oceanologic manifestations of certain science topics. Included are teacher guides, student activities, and demonstrations designed to impart ocean understanding to high school students. When the student has completed this unit, he should be able to: (1) define an…

  6. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2005

    SciTech Connect

    Diefenderfer, Heida L.; Thom, Ronald M.; Borde, Amy B.; Roegner, G. C.; Whiting, Allan H.; Johnson, Gary E.; Dawley, Earl; Skalski, John R.; Vavrinec, John; Ebberts, Blaine D.

    2006-12-20

    This report is the second annual report of a six-year project to evaluate the cumulative effects of habitat restoration projects in the Columbia River Estuary, conducted by Pacific Northwest National Laboratory's Marine Sciences Laboratory, NOAA's National Marine Fisheries Service Pt. Adams Biological Field Station, and the Columbia River Estuary Study Taskforce for the US Army Corps of Engineers. In 2005, baseline data were collected on two restoration sites and two associated reference sites in the Columbia River estuary. The sites represent two habitat types of the estuary--brackish marsh and freshwater swamp--that have sustained substantial losses in area and that may play important roles for salmonids. Baseline data collected included vegetation and elevation surveys, above and below-ground biomass, water depth and temperature, nutrient flux, fish species composition, and channel geometry. Following baseline data collection, three kinds of restoration actions for hydrological reconnection were implemented in several locations on the sites: tidegate replacements (2) at Vera Slough, near the city of Astoria in Oregon State, and culvert replacements (2) and dike breaches (3) at Kandoll Farm in the Grays River watershed in Washington State. Limited post-restoration data were collected: photo points, nutrient flux, water depth and temperature, and channel cross-sections. In subsequent work, this and additional post-restoration data will be used in conjunction with data from other sites to estimate net effects of hydrological reconnection restoration projects throughout the estuary. This project is establishing methods for evaluating the effectiveness of individual projects and a framework for assessing estuary-wide cumulative effects including a protocol manual for monitoring restoration and reference sites.

  7. Engines for the future

    Microsoft Academic Search

    A. W. Jr. Reitze; G. L. Reitze

    1976-01-01

    Studies on the alternatives to the spark ignition internal combustion engine are summarized. Alternatives reviewed include: electric and hybrid engines, Rankine cycle steam engine, Stirling engine, Brayton (gas turbine) engine, diesel engine, and the stratified charge engine. Advantages, disadvantages, and feasibility of each are reviewed. (ND)

  8. United States Air Force 611th Air Support Group/Civil Engineering Squadron Elmendorf AFB, Alaska. Remedial investigation and feasibility study. Bullen Point Radar Installation, Alaska. Final report

    SciTech Connect

    Karmi, S.

    1996-03-18

    The United States Air Force (Air Force) has prepared this Remedial investigation/Feasibility Study (RI/FS) report as part of the Installation Restoration Program (IRP) to present results of RI/FS activities at five sites at the Bullen Point radar installation. The IRP provides for investigating, quantifying, and remediating environmental contamination from past waste management activities at Air Force installations throughout the United States.

  9. ESTIMATING THE CONDITION OF GULF OF MEXICO ESTUARIES: NATIONAL COASTAL ASSESSMENT AND NATIONAL ESTUARY PROGRAM

    EPA Science Inventory

    Estuaries in the Gulf of Mexico have been monitored since 1991 to determine the condition of water, sediment, and biota. More recently, through the National Coastal Assessment (NCA), U.S. EPA has provided a comprehensive estimate of the condition of U.S. estuaries, including a re...

  10. A trophic model for the Danshuei River Estuary, a hypoxic estuary in northern Taiwan.

    PubMed

    Lin, Hsing-Juh; Shao, Kwang-Tsao; Jan, Rong-Quen; Hsieh, Hwey-Lian; Chen, Chang-Po; Hsieh, Li-Yung; Hsiao, Yi-Ting

    2007-11-01

    The estuary of the Danshuei River, a hypoxic subtropical estuary, receives a high rate of untreated sewage effluent. The Ecopath with Ecosim software system was used to construct a mass-balanced trophic model for the estuary, and network analysis was used to characterize the structure and matter flow in the food web. The estuary model was comprised of 16 compartments, and the trophic levels varied from 1.0 for primary producers and detritus to 3.0 for carnivorous and piscivorous fishes. The large organic nutrient loading from the upper reaches has resulted in detritivory being more important than herbivory in the food web. The food-chain length of the estuary was relatively short when compared with other tropical/subtropical coastal systems. The shortness of food-chain length in the estuary could be attributed to the low biomass of the top predators. Consequently, the trophic efficiencies declined sharply for higher trophic levels due to low fractions of flows to the top predators and then high fractions to detritus. The low biomass of the top predators in the estuary was likely subject to over-exploitation and/or hypoxic water. Summation of individual rate measurements for primary production and respiration yielded an estimate of -1791 g WW m(-2) year(-1), or -95 g C m(-2) year(-1), suggesting a heterotrophic ecosystem, which implies that more organic matter was consumed than was produced in the estuary. PMID:17826803

  11. MOBILE BAY NATIONAL ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN

    EPA Science Inventory

    In simplest terms, an estuary is defined as an area where rivers meet the sea. They are transitional zones where freshwater rivers meet tidally influenced marine waters. Estuaries are considered environmentally and economically important because of their exceptional biological di...

  12. Transport of particulate organic material between salt marsh and estuary

    Microsoft Academic Search

    W. J. Wolff

    1979-01-01

    The macrophyte production and the transport of particulate organic matter between march and adjacent estuary have been investigated for a 30 ha salt marsh along the Oosterschelde estuary, The Netherlands.

  13. United States Air Force 611th Air Support Group Civil Engineering Squadron, Elmendorf AFB, Alaska. Remedial investigation and feasibility study Point Lay Radar Installation, Alaska. Final report

    SciTech Connect

    Karmi, S.

    1996-03-04

    The United States Air Force (Air Force) has prepared this Remedial Investigation/Feasibility Study (RI/FS) report to present the results of RI/FS activities at four sites located at the Point Lay radar installation. The remedial investigation (RI) field activities were conducted at the Point Lay radar installation during the summer of 1993. The four sites at Point Lay were investigated because they were suspected of being contaminated with hazardous substances. RI activities were conducted using methods and procedures specified in the RI/FS Work Plan, Sampling and Analysis Plan (SAP), and Health and Safety Plan.

  14. The Estuary Guide. Level 3: High School. Draft.

    ERIC Educational Resources Information Center

    Alexander, Glen; And Others

    Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the high school level seeks to teach what estuaries are; provide opportunities to practice decision-making that affects estuaries; and encourage students to…

  15. SAN FRANCISCO ESTUARY PROJECT COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN

    EPA Science Inventory

    The Estuary, a significant natural resource, San Francisco Bay and the Delta combine to form the West Coast's largest estuary. The Estuary conveys the waters of the Sacramento and San Joaquin Rivers to the Pacific Ocean. It encompasses roughly 1,600 square miles, drains over 40 p...

  16. Monitoring and Managing Contamination in the San Francisco Estuary

    E-print Network

    relevant. Introductory information on what is measured by the RMP and why can be found in the 1998 Pulse2000Update Monitoring and Managing Contamination in the San Francisco Estuary of the Estuary Pulse, California. The Pulse of the Estuary is one of three Regional Monitoring Program reporting products for 2000

  17. Environmental flow assessments for transformed estuaries

    NASA Astrophysics Data System (ADS)

    Sun, Tao; Zhang, Heyue; Yang, Zhifeng; Yang, Wei

    2015-01-01

    Here, we propose an approach to environmental flow assessment that considers spatial pattern variations in potential habitats affected by river discharges and tidal currents in estuaries. The approach comprises four steps: identifying and simulating the distributions of critical environmental factors for habitats of typical species in an estuary; mapping of suitable habitats based on spatial distributions of the Habitat Suitability Index (HSI) and adopting the habitat aggregation index to understand fragmentation of potential suitable habitats; defining variations in water requirements for a certain species using trade-off analysis for different protection objectives; and recommending environmental flows in the estuary considering the compatibility and conflict of freshwater requirements for different species. This approach was tested using a case study in the Yellow River Estuary. Recommended environmental flows were determined by incorporating the requirements of four types of species into the assessments. Greater variability in freshwater inflows could be incorporated into the recommended environmental flows considering the adaptation of potential suitable habitats with variations in the flow regime. Environmental flow allocations should be conducted in conjunction with land use conflict management in estuaries. Based on the results presented here, the proposed approach offers flexible assessment of environmental flow for aquatic ecosystems that may be subject to future change.

  18. Comparasion of finite difference and finite element hydrodynamic models applied to the Laguna Madre Estuary, Texas

    E-print Network

    McArthur, Karl Edward

    1996-01-01

    Madre Estuary . . General Hydrodynamic Modeling. . Previous Studies in the Laguna Madre . TxBLEND and SWIFI2D. . III DESCRIPTION OF MODELS . SWIFT2D TxBLEND . . Data Bathymetry Generation . . Grid Cell Size Selecdon. Simulation . . Calibration... developed by the U. S. Army Corps of Engineers Waterways Experiment Station hydraulic group has been used in a number of applications. The TABS system is comprised of the Geometry File Generation program (GFGEN), RMA2, RMA4, and SED2D. The GFGEN software...

  19. Multi-Scale Action Effectiveness Research in the Lower Columbia River and Estuary, 2012

    SciTech Connect

    Johnson, Gary E.; Sather, Nichole K.; Storch, Adam; Johnson, Jeff; Skalski, J. R.; Teel, D. J.; Brewer, Taylor; Bryson, Amanda J.; Dawley, Earl M.; Kuligowski, D. R.; Whitesel, T.; Mallette, Christine

    2013-11-30

    The study reported herein was conducted for the U.S. Army Corps of Engineers, Portland District (USACE) by researchers at the Pacific Northwest National Laboratory (PNNL), Oregon Department of Fish and Wildlife (ODFW), National Marine Fisheries Service (NMFS), University of Washington (UW), and U.S. Fish and Wildlife Service (USFWS). The goal of the study was to evaluate the ecological benefits of restoration actions for juvenile salmon in the lower Columbia River and estuary (LCRE; rkm 0–234).

  20. Evaluation of Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2010

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L.; Thom, Ronald M.; Roegner, G. Curtis; Ebberts, Blaine D.; Skalski, John R.; Borde, Amy B.; Dawley, Earl; Coleman, Andre M.; Woodruff, Dana L.; Breithaupt, Stephen A.; Cameron, April; Corbett, C.; Donley, Erin E.; Jay, D. A.; Ke, Yinghai; Leffler, K.; McNeil, C.; Studebaker, Cindy; Tagestad, Jerry D.

    2012-05-01

    This is the seventh and final annual report of a project (2004–2010) addressing evaluation of the cumulative effects of habitat restoration actions in the 235-km-long lower Columbia River and estuary. The project, called the Cumulative Effects (CE) study, was conducted for the U.S. Army Corps of Engineers Portland District by a collaboration of research agencies led by the Pacific Northwest National Laboratory. We achieved the primary goal of the CE study to develop a methodology to evaluate the cumulative effects of habitat actions in the Columbia Estuary Ecosystem Restoration Program. We delivered 1) standard monitoring protocols and methods to prioritize monitoring activities; 2) the theoretical and empirical basis for a CE methodology using levels-of-evidence; 3) evaluations of cumulative effects using ecological relationships, geo-referenced data, hydrodynamic modeling, and meta-analyses; and 4) an adaptive management process to coordinate and coalesce restoration efforts in the LCRE. A solid foundation has been laid for future comprehensive evaluations of progress made by the Columbia Estuary Ecosystem Restoration Program to understand, conserve, and restore ecosystems in the lower Columbia River and estuary.

  1. JOURNAL OF INFORMATION SCIENCE AND ENGINEERING 28, 723-737 (2012) A Trace-Based Feasibility Study of Infrastructure-Less VoIP

    E-print Network

    Lyuu, Yuh-Dauh

    2012-01-01

    Study of Infrastructure-Less VoIP KUN-CHAN LAN AND TSUNG-HSUNG WU Department of Computer Science and Information Engineering National Cheng Kung University Tainan, 804 Taiwan Voice over IP (VoIP) is one of the most popular Internet applications. Many VoIP protocols (e.g. SIP) are based on a central-server scheme

  2. Facilitation of the Estuary/Ocean Subgroup and the Expert Regional Technical Group, Fiscal Year 2014 Annual Report

    SciTech Connect

    Johnson, Gary E.

    2014-09-01

    This document is the annual report for fiscal year 2014 for the project called Facilitation of the Estuary/Ocean Subgroup (EOS) and the Expert Regional Technical Group (ERTG). Pacific Northwest National Laboratory (PNNL) conducted the project for the Bonneville Power Administration. The EOS and ERTG are part of the research, monitoring, and evaluation and habitat restoration efforts, respectively, developed by the Action Agencies (BPA, U.S. Army Corps of Engineers) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System and implemented under the Columbia Estuary Ecosystem Restoration Program.

  3. Modeling tidal distortion in the Ogeechee Estuary

    NASA Astrophysics Data System (ADS)

    Bruder, Brittany; Bomminayuni, Sandeep; Haas, Kevin; Stoesser, Thorsten

    2014-10-01

    A 3D numerical model is used to simulate the distortion of tidal hydrodynamics in the Ogeechee Estuary, GA. The Ogeechee, like many estuaries found in the Southeastern US, consists of shallow channel networks and extensive intertidal storage in the form of wetlands. Such features are known to induce non-linear overtide generation and significant tidal distortion, otherwise known as tidal stage asymmetry. Simulations are run with varying parameters to assess their effects on modeling tidal distortion for the Ogeechee Estuary: bottom friction coefficients, enhanced wetland friction coefficients, and tidal flat elevations. To succinctly quantify the degree of distortion across the domain, the statistical parameters of skewness and asymmetry are calculated for time series of water surface heights and channel volume fluxes. The intertidal storage causes the peak flood flux to occur later and the peak ebb flux to occur earlier, thereby resulting in positive asymmetry for the volume flux for the full estuary. However, ebb dominance is a localized feature and varies throughout the estuary. Increasing the intertidal storage by lowering wetland elevation enhances the effects on high tide and volume flux magnitudes, decreasing the ebb-dominance and volume flux asymmetry typically associated with intertidal storage thereby indicating the importance of the wetland elevation over the total storage volume. Increased channel bottom friction reduces ebb-dominance by extending the duration of the falling tide. More interestingly, increased wetland friction reduces the influence of wetland intertidal storage on tidal distortion. The model suggests an increase in wetland friction does little to dampen wave propagation at high tide but rather impedes the lateral flooding of wetlands, reducing ebb dominance. Tidal flat elevation has the largest impact on distortion for the Ogeechee Estuary whereas enhanced wetland and bottom frictional influences on distortion are small, albeit not insignificant.

  4. Decadal mercury trends in San Francisco Estuary sediments.

    PubMed

    Conaway, Christopher H; Ross, John R M; Looker, Richard; Mason, Robert P; Flegal, A Russell

    2007-09-01

    Monitoring sediment quality and total mercury concentrations over the period 1993-2001 at 26 stations in San Francisco Estuary has shown the seasonal cycling of mercury sediment concentrations, as well as a significant (P < 0.05) decrease in those concentrations at eight stations across the estuary. This decrease in sediment mercury concentrations is attributed to the transport of relatively cleaner sediment to the estuary from the Sacramento River and San Joaquin River watersheds. Despite the decreases observed in some parts of the estuary, no corresponding trend has been found in concurrent studies on sport fish and bivalves in the estuary. PMID:17161835

  5. Feasibility of xylose fermentation by engineered Saccharomyces cerevisiae overexpressing endogenous aldose reductase (GRE3), xylitol dehydrogenase (XYL2), and xylulokinase (XYL3) from Scheffersomyces stipitis.

    PubMed

    Kim, Soo Rin; Kwee, Nathania R; Kim, Heejin; Jin, Yong-Su

    2013-05-01

    Saccharomyces cerevisiae has been engineered for producing ethanol from xylose, the second most abundant sugar in cellulosic biomass hydrolyzates. Heterologous expressions of xylose reductase (XYL1) and xylitol dehydrogenase (XYL2), or of xylose isomerase (xylA), either case of which being accompanied by overexpression of xylulokinase (XKS1 or XYL3), are known as the prevalent strategies for metabolic engineering of S. cerevisiae to ferment xylose. In this study, we propose an alternative strategy that employs overexpression of GRE3 coding for endogenous aldose reductase instead of XYL1 to construct efficient xylose-fermenting S. cerevisiae. Replacement of XYL1 with GRE3 has been regarded as an undesirable approach because NADPH-specific aldose reductase (GRE3) would aggravate redox balance with xylitol dehydrogenase (XYL2) using NAD(+) exclusively. Here, we demonstrate that engineered S. cerevisiae overexpressing GRE3, XYL2, and XYL3 can ferment xylose as well as a mixture of glucose and xylose with higher ethanol yields (0.29-0.41 g g(-1) sugars) and productivities (0.13-0.85 g L(-1) h(-1)) than those (0.23-0.39 g g(-1) sugars, 0.10-0.74 g L(-1) h(-1)) of an isogenic strain overexpressing XYL1, XYL2, and XYL3 under oxygen-limited conditions. We found that xylose fermentation efficiency of a strain overexpressing GRE3 was dramatically increased by high expression levels of XYL2. Our results suggest that optimized expression levels of GRE3, XYL2, and XYL3 could overcome redox imbalance during xylose fermentation by engineered S. cerevisiae under oxygen-limited conditions. PMID:23398717

  6. Feasibility of husk-fuelled steam engines as prime mover of grid-connected generators under the Thai very small renewable energy power producer (VSPP) program

    Microsoft Academic Search

    Chanoknun Sookkumnerd; Nobutaka Ito; Koji Kito

    2007-01-01

    Rice husk generated as a by-product of rice mill processes can be utilized as an energy source for husk-fuelled rice mills. The economic evaluation of the investment of husk-fuelled steam engine rice mills, which generate mechanical energy for the direct driving of milling equipments, has previously been presented in literature. It was reported that for some particular conditions of rice

  7. Detection of estuarine and tidal river hydromorphology using hyper-spectral and LiDAR data: Forth estuary, Scotland

    NASA Astrophysics Data System (ADS)

    Gilvear, David; Tyler, Andrew; Davids, Corine

    2004-11-01

    High spatial resolution hyper-spectral imagery (CASI) and light detection and ranging (LiDAR) imagery acquired for the tidal River Carron and Forth estuary, Scotland, were used in conjunction with field surveys to assess the feasibility of monitoring hydromorphology and human alterations with satellite and airborne remote sensing data. The study was undertaken in the context of the European Union Water Framework Directive (WFD) that requires member states to monitor hydromorphological elements as a component of the ecological status of rivers, estuaries and shorelines. Visual assessment and automated classifications of the imagery were compared with field survey data for an estuarine reach comprising saline waters, mudflats, a tidal reach of a tributary river and an urban/industrialised shoreline. The morphology of the estuary and inflowing tidal waters together with most artificial features of interest could be clearly seen in the CASI imagery at 1 m spatial resolution. Supervised classification of the imagery produced an overall accuracy value of 72%. Downgrading the imagery to simulate the spatial resolution of 4 m IKONOS satellite data surprisingly improved the accuracy to 74%. Simulation of 10 m SPOT imagery resulted in an image where many artificial features of interest such as roads, pipelines and jetties were rendered invisible. Adding LiDAR data as an additional data set aided manual and automated identification of features and visualisation of the hydromorphology of the rivers and estuaries in the study area. Shadows cast from tall objects were a feature of the winter imagery and reduced automated classification accuracy. Overall, the study demonstrates that high spatial resolution remotely sensed digital imagery has the potential to be a useful tool for panoptic mapping of the geomorphology and human impact on tidal rivers and estuaries. In the context of the WFD, remote sensing provides a potential way forward for monitoring the physical status of rivers and estuaries at the national scale. The possibilities and constraints, in light of the findings of this study, are discussed.

  8. Facilitation of the Estuary/Ocean Subgroup and the Expert Regional Technical Group, Fiscal Year 2013 Annual Report

    SciTech Connect

    Johnson, Gary E.; Sather, Nichole K.

    2013-10-30

    This project covers facilitation of the Estuary/Ocean Subgroup (EOS) for federal research, monitoring, and evaluation (RME) and the Expert Regional Technical Group (ERTG) for estuary habitat restoration. The EOS is part of the research, monitoring, and evaluation effort that the Action Agencies (Bonneville Power Administration [BPA], U.S. Army Corps of Engineers [Corps], U.S. Bureau of Reclamation) developed in response to obligations arising from the Endangered Species Act as applied to operation of the Federal Columbia River Power System (FCRPS). The EOS is tasked by National Marine Fisheries Service (NMFS) and the Action Agencies (AAs) to design and coordinate implementation of the federal RME plan for the lower Columbia River and estuary, including the river’s plume in the ocean. Initiated in 2002, the EOS is composed of members from BPA, the Corps, NMFS, and Pacific Northwest National Laboratory’s (PNNL’s) Marine Sciences Laboratory, and other agencies as necessary.

  9. RIVERINE ESTUARY CLASSIFICATION FOR THE SAKE OF ENVIRONMENTAL CONSERVATION

    NASA Astrophysics Data System (ADS)

    Kishida, Hiroyuki; Amano, Kunihiko; Oonuma, Katsuhiro; Endoh, Maremi

    The environment of riverine estuaries is characterized by many factors including tidal oscillation, river flow and morphology, and the combination of these factors makes each estuary unique in its environment. However, there are similarities among some estuaries. We have tried to classify Japan’s 109 riverine estuaries based on physical environmental factors like tidal oscillation, wave energy, and high and low river flow. 109 riverine estuaries were divided into 5 classifications. Fish species monitoring data have also been analyzed to categorize riverine estuaries and the results were compared to 5 classifications divided by physical factors. Since our physical and biological classification both seemed to be related to the salinity of the estuary, these two classifications showed fair conformity.

  10. PECONIC ESTUARY: AN ASSESSMENT OF SHELLFISH RESOURCES IN THE TRIBUTARIES AND EMBAYMENTS OF THE PECONIC ESTUARY

    EPA Science Inventory

    Executive Summary Historically, the Peconic Estuary's shellfish resources have supported significant fisheries for a number of species including hard clams, oysters and bay scallops. However, distribution and abundance data for the tributaries and embayments within the Peconic Es...

  11. Comet nucleus impact probe feasibility study

    NASA Technical Reports Server (NTRS)

    Castro, A. J.

    1980-01-01

    A top level listing of the comet nucleus impact probe (CNIP) feasibility experiments requirements are presented. A conceptual configuration which shows that the feasibility of engineering the experiment is possible and describes the candidate hardware is discussed. The design studies required in order to design the operating experiment are outlined. An overview of a program plan used to estimate a rough order of magnitude cost for the CNIP experiment is given.

  12. Remedial investigation/feasibility study Work Plan and addenda for Operable Unit 4-12: Central Facilities Area Landfills II and III at the Idaho National Engineering Laboratory

    SciTech Connect

    Keck, K.N.; Stormberg, G.J.; Porro, I.; Sondrup, A.J.; McCormick, S.H.

    1993-07-01

    This document is divided into two main sections -- the Work Plan and the addenda. The Work Plan describes the regulatory history and physical setting of Operable Unit 4-12, previous sampling activities, and data. It also identifies a preliminary conceptual model, preliminary remedial action alternatives, and preliminary applicable or relevant and appropriate requirements. In addition, the Work Plan discusses data gaps and data quality objectives for proposed remedial investigation activities. Also included are tasks identified for the remedial investigation/feasibility study (RI/FS) and a schedule of RI/FS activities. The addenda include details of the proposed field activities (Field Sampling Plan), anticipated quality assurance activities (Quality Assurance Project Plan), policies and procedures to protect RI/FS workers and the environment during field investigations (Health and Safety Plan), and policies, procedures, and activities that the Department of Energy will use to involve the public in the decision-making process concerning CFA Landfills II and III RI/FS activities (Community Relations Plan).

  13. Baseline ecological risk assessment of the Calcasieu Estuary, Louisiana: 1. Overview and problem formulation

    USGS Publications Warehouse

    MacDonald, Donald D.; Moore, Dwayne R.J.; Ingersoll, Christopher G.; Smorong, Dawn E.; Carr, R. Scott; Gouguet, Ron; Charters, David; Wilson, Duane; Harris, Tom; Rauscher, Jon; Roddy, Susan; Meyer, John

    2011-01-01

    A remedial investigation/feasibility study (RI/FS) of the Calcasieu Estuary cooperative site was initiated in 1998. This site, which is located in the southwestern portion of Louisiana in the vicinity of Lake Charles, includes the portion of the estuary from the saltwater barrier on the Calcasieu River to Moss Lake. As part of the RI/FS, a baseline ecological risk assessment (BERA) was conducted to assess the risks to aquatic organisms and aquatic-dependent wildlife exposed to environmental contaminants. The purpose of the BERA was to determine if adverse effects on ecological receptors are occurring in the estuary; to evaluate the nature, severity, and areal extent of any such effects; and to identify the substances that are causing or substantially contributing to effects on ecological receptors. This article describes the environmental setting and site history, identifies the chemicals of potential concern, presents the exposure scenarios and conceptual model for the site, and summarizes the assessment and measurement endpoints that were used in the investigation. Two additional articles in this series describe the results of an evaluation of effects-based sediment-quality guidelines as well as an assessment of risks to benthic invertebrates associated with exposure to contaminated sediment.

  14. VOLUNTEER ESTUARY MONITORING: A METHOD MANUAL

    EPA Science Inventory

    Executive Summary: This manual focuses on volunteer estuary monitoring. As concern over the well-being of the environment has increased during the past couple of decades, volunteer monitoring has become an integral part of the effort to assess the health of our nation’s wat...

  15. DELAWARE ESTUARY PROGRAM IMPLEMENTATION STREAMLINE REVIEW, 2002

    EPA Science Inventory

    The primary purpose of the Delaware Estuary Program implementation review (formerly known as the biennial review) has been to assist EPA in. making funding decisions for those NEPs that are in the post-CCMP, or implementation, phase, and to evaluate implementation progress. The i...

  16. BATHYMETRY FOR ALBEMARLE AND PAMLICO ESTUARIES, NC

    EPA Science Inventory

    Bathymetry for the Albemarle and Pamlico Estuaries obtained from National Oceanographic and Atmospheric Administration-National Ocean Service (NOAA-NOS). See the metadata within the files from NOAA-NOS for more details and warnings concerning merging with US Geolgoical Survey Dig...

  17. Padilla Bay: The Estuary Guide. Level 2.

    ERIC Educational Resources Information Center

    Friesem, Judy; Lynn, Valerie, Ed.

    Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the middle school level is designed for use with the on-site program developed by the Padilla Bay National Esturine Research Reserve (Washington). The guide…

  18. BCG Approaches for Improved Management of Estuaries

    EPA Science Inventory

    Estuaries and other complex aquatic systems are exposed to a variety of stressors that act at several scales, but are managed piecemeal - - often resulting in a ?death by 1000 cuts? caused by cumulative impacts to these valued resources. To address this, managers need tools that...

  19. INDICATORS OF ECOSYSTEM INTEGRITY FOR ESTUARIES

    EPA Science Inventory

    Jordan, Stephen J. and Lisa M. Smith. In press. Indicators of Ecosystem Integrity for Estuaries. In: Proceedings of the Estuarine Indicators Workshop, 29-31 October 2003, Sanibel Island, FL. Sanibel-Captiva Conservation Foundation, Sanibel, FL. 23 p. (ERL,GB 1194). Ideal ...

  20. Estuaries and Tidal Marshes. Habitat Pac.

    ERIC Educational Resources Information Center

    Fish and Wildlife Service (Dept. of Interior), Washington, DC.

    This educational packet consists of an overview, three lesson plans, student data sheets, and a poster. The overview examines estuaries and tidal or salt marshes by discussing the plants and animals in these habitats, marsh productivity, benefits and management of the habitats, historical aspects, and development and pollution. A glossary and list…

  1. Adsorption processes and hydrodynamic conditions in estuaries

    Microsoft Academic Search

    W. Salomons

    1980-01-01

    In estuaries the decrease in adsorption of dissolved metals to suspended particulate matter is counteracted by more or less simultaneous increases in turbidity, pH and by the formation of new particulate matter. Experiments on the behaviour of cadmium and zinc under artificial estuarine conditions show that the processes in the region of 0–5% chlorinity are most important.

  2. Kaua'i: Streams and Estuaries.

    ERIC Educational Resources Information Center

    Hawkins, John, Ed.; Murakami, Colleen, Ed.

    Designed to help teachers develop students' awareness and understanding of some of Hawaii's endangered aquatic resources, this module contains activities and instructional suggestions for use with intermediate as well as high school students. The module is divided into two sections which explore the streams and estuaries of Kauai. Activities in…

  3. THE ECOLOGICAL CONDITION OF VERACRUZ, MEXICO ESTUARIES

    EPA Science Inventory

    During June and July, 2002, forty-seven stations were sampled within estuaries along the gulf coast of the state of Veracruz, MX, using a probabilistic survey design and a common set of response indicators. The objective of the study was to collect information to assess the condi...

  4. Introduction In many estuaries of North America,

    E-print Network

    shoreline flats. The principal mat-form- ing types are sea lettuce, Ulva lactuca (Fig. 1), Enteromorpha spp., Gracilaria spp., and Cladophora spp. Few macroin- Removal of Sea Lettuce, Ulva spp., in Estuaries to Improve--Mats (biomasses) of mac- roalgae, i.e. Ulva spp., Enteromorpha spp., Graciolaria spp., and Cladophora spp., have

  5. Climate change and its impacts on estuaries

    EPA Science Inventory

    Past, present, and future research by WED scientists in the TEP region will be described to lay the foundation for examination of potential climate change effects on estuaries and the broader coastal zone in the Pacific Northwest (PNW). Results from National Coastal Assessments,...

  6. TAMPA BAY ESTUARY PROGRAM, 2004 IMPLEMENTATION REVIEW

    EPA Science Inventory

    The Tampa Bay Estuary Program and its partners have made measurable progress toward implementation of the adopted CCMP goals. Progress has occurred in the following areas: bay habitats, with an increase in seagrass, estuarine habitat restoration and preservation; water and sedime...

  7. ENGINEERING FEASIBILITY AND ECONOMICS OF CO2 SEQUESTRATION/USE ON AN EXISTING COAL-FIRED POWER PLANT: A LITERATURE REVIEW

    SciTech Connect

    Carl R. Bozzuto; Nsakala ya Nsakala

    2000-01-31

    The overall objective of this study is to evaluate the technical feasibility and the economics of alternate CO{sub 2} capture and sequestration/use technologies for retrofitting an existing pulverized coal-fired power plant. To accomplish this objective three alternative CO{sub 2} capture and sequestration systems will be evaluated to identify their impact on an existing boiler, associated boiler auxiliary components, overall plant operation and performance and power plant cost, including the cost of electricity. The three retrofit technologies that will be evaluated are as follows: (1) Coal combustion in air, followed by CO{sub 2} separation from flue gas with Kerr-McGee/ABB Lummus Global's commercial MEA-based absorption/stripping process. (2) Coal combustion in an O{sub 2}/CO{sub 2} environment with CO{sub 2} recycle. (3) Coal combustion in air with oxygen removal and CO{sub 2} captured by tertiary amines In support of this objective and execution of the evaluation of the three retrofit technologies a literature survey was conducted. It is presented in an ''annotated'' form, consistent with the following five sections: (1) Coal Combustion in O{sub 2}/CO{sub 2} Media; (2) Oxygen Separation Technologies; (3) Post Combustion CO{sub 2} Separation Technologies; (4) Potential Utilization of CO{sub 2}; and (5) CO{sub 2} Sequestration. The objective of the literature search was to determine if the three retrofit technologies proposed for this project continue to be sound choices. Additionally, a review of the literature would afford the opportunity to determine if other researchers have made significant progress in developing similar process technologies and, in that context, to revisit the current state-of-the-art. Results from this literature survey are summarized in the report.

  8. Geothermal feasibility study for Malting Investments Inc

    SciTech Connect

    Not Available

    1981-10-01

    The engineering feasibility of using geothermal heat in the kilning, germination, and steep water cooling processes for a malting facility is determined. The study is based upon a malting facility with an annual capacity of malting three million bushels of clean graded barley per year or 8220 bushels per day. Capital cost figures used in the feasibility study are budget prices for the basic equipment only, they do not include any other costs such as installation, instrumentation or design and engineering costs. Utility prices are based upon $0.03 per kilowatt hour and $0.4548 per therm for natural gas.

  9. Thank you to our sponsors Thinking about healthy estuaries in the Year 2111 and

    E-print Network

    made in the catchment are disconnected from estuary health #12 estuaries? · Swan-Canning Estuary: 90% of people agreed or strongly agreed that the rivers are a really important part of Perth's landscape, 97% that natural areas

  10. 76 FR 8345 - Endangered and Threatened Species; Recovery Plan Module for Columbia River Estuary Salmon and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-14

    ...Species; Recovery Plan Module for Columbia River Estuary Salmon and Steelhead AGENCY: National...availability; recovery plan module for Columbia River estuary salmon and steelhead...announces the adoption of the Columbia River Estuary Endangered Species Act...

  11. 75 FR 17382 - Small Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Water...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-06

    ...Incidental to Specified Activities; Russian River Estuary Water Level Management Activities...Level B harassment, incidental to Russian River Estuary (Estuary) water level management...activities at the mouth of the Russian River, Jenner, CA. DATES: Effective...

  12. San Francisco Estuary Regional Monitoring Program for Trace Substances A Review of Urban Runoff Processes

    E-print Network

    San Francisco Estuary Regional Monitoring Program for Trace Substances A Review of Urban Runoff Pathways and Loadings Workgroup (SPLWG) San Francisco Estuary Regional Monitoring Program for Trace and Loading Workgroup. San Francisco Estuary Regional Monitoring Program for Trace Substances. SFEI

  13. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2006

    SciTech Connect

    Johnson, Gary E.; Borde, Amy B.; Dawley, Earl; Diefenderfer, Heida L.; Ebberts, Blaine D.; Putman, Douglas A.; Roegner, G. C.; Thom, Ronald M.; Vavrinec, John; Whiting, Allan H.

    2007-12-06

    This report is the third annual report of a six-year project to evaluate the cumulative effects of habitat restoration action in the Columbia River Estuary (CRE). The project is being conducted for the U.S. Army Corps of Engineers (Corps) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory, the Pt. Adams Biological Field Station of the National Marine Fisheries Service, and the Columbia River Estuary Study Taskforce. Measurement of the cumulative effects of ecological restoration projects in the Columbia River estuary is a formidable task because of the size and complexity of the estuarine landscape and the meta-populations of salmonids in the Columbia River basin. Despite the challenges presented by this system, developing and implementing appropriate indicators and methods to measure cumulative effects is the best way to enable estuary managers to track the overall effectiveness of investments in estuarine restoration projects. This project is developing methods to quantify the cumulative effects of multiple restoration activities in the CRE. The overall objectives of the 2006 study were to continue to develop techniques to assess cumulative effects, refine the standard monitoring protocols, and initiate development of an adaptive management system for Corps of Engineers’ habitat restoration monitoring efforts in the CRE. (The adaptive management effort will be reported at a later date.) Field studies during 2006 were conducted in tidal freshwater at Kandoll Farm on the lower Grays River and tidal brackish water at Vera Slough on Youngs Bay. Within each of area, we sampled one natural reference site and one restoration site. We addressed the overall objectives with field work in 2006 that, coupled with previous field data, had specific objectives and resulted in some important findings that are summarized here by chapter in this report. Each chapter of the report contains data on particular monitored variables for pre- and post-restoration conditions at both the Kandoll and Vera study areas.

  14. Historical changes in the Columbia River Estuary

    NASA Astrophysics Data System (ADS)

    Sherwood, Christopher R.; Jay, David A.; Bradford Harvey, R.; Hamilton, Peter; Simenstad, Charles A.

    Historical changes in the hydrology, sedimentology, and physical oceanography of the Columbia River Estuary have been evaluated with a combination of statistical, cartographic, and numerical-modelling techniques. Comparison of data digitized from US Coast and Geodetic Survey bathymetric surveys conducted in the periods 1867-1875, 1926-1937, and 1949-1958 reveals that large changes in the morphology of the estuary have been caused by navigational improvements (jetties, dredged channels, and pile dikes) and by the diking and filling of much of the wetland area. Lesser changes are attributable to natural shoaling and erosion. There has been roughly a 15% decrease in tidal prism and a net accumulation of about 68 × 10 6m 3 of sediment in the estuary. Large volumes of sediment have been eroded from the entrance region and deposited on the continental shelf and in the balance of the estuary, contributing to formation of new land. The bathymetric data indicate that, ignoring erosion at the entrance, 370 to 485 × 10 6m 3 of sediment has been deposited in the estuary since 1868 at an average rate of about 0.5 cm y -1, roughly 5 times the rate at which sea level has fallen locally since the turn of the century. Riverflow data indicate that the seasonal flow cycle of the Columbia River has been significantly altered by regulation and diversion of water for irrigation. The greatest changes have occurred in the last thirty years. Flow variability over periods greater than a month has been significantly damped and the net discharge has been slightly reduced. These changes in riverflow are too recent to be reflected in the available in the available bathymetric data. Results from a laterally averaged, multiple-channel, two-dimensional numerical flow model (described in HAMILTON, 1990) suggest that the changes in morphology and riverflow have reduced mixing, increased stratification, altered the response to fortnightly (neap-spring) changes in tidal forcing, and decreased the salinity intrusion length and the transport of salt into the estuary. The overall effects of human intervention in the physical processes of the Columbia River Estuary (i.e. decrease in freshwater inflow, tidal prism, and mixing; increase in flushing time and fine sediment deposition, and net accumulation of sediment) are qualitatively similar to those observed in less energetic and more obviously altered estuarine systems. A concurrent reduction in wetland habitats has resulted in an estimated 82% reduction in emergent plant production and a 15% reduction in benthic macroalgae production, a combined production loss of 51,675 metric tons of organic carbon per year. This has been at least partially compensated by a large increase in the supply of riverine detritus derived from freshwater phytoplankton primary production. Comparison of modern and estimated preregulation organic carbon budgets for the estuary indicates a shift from a food web based on comparatively refractory macrodetritus derived from emergent vegetation to one involving more labile microdetritus derived from allochthonous phytoplankton. The shift has been driven by human-induced changes to the physical environment of the estuary. While this is a relatively comprehensive study of historical physical changes, it is incomplete in that the sediment budget is still uncertain. More precise quantification of the modern estuarine sediment budget will require both a better understanding of the fluvial input and dredging export terms and a sediment tranport model designed to explain historical changes in the sediment budget. Oceanographic studies to better determine the mechanisms leading to the formation of the turbidity maximum are also needed. The combination of cartography and modelling used in this study should be applicable in other systems where large changes in morphology have occurred in historical time.

  15. Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2010

    SciTech Connect

    Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, J. R.; Dawley, Earl M.; Coleman, Andre M.; Ostrand, Kenneth G.; Hanson, Kyle C.; Woodruff, Dana L.; Donley, Erin E.; Ke, Yinghai; Buenau, Kate E.; Bryson, Amanda J.; Townsend, Richard L.

    2011-10-01

    This report describes the 2010 research conducted under the U.S. Army Corps of Engineers (USACE) project EST-P-09-1, titled Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, and known as the 'Salmon Benefits' study. The primary goal of the study is to establish scientific methods to quantify habitat restoration benefits to listed salmon and trout in the lower Columbia River and estuary (LCRE) in three required areas: habitat connectivity, early life history diversity, and survival (Figure ES.1). The general study approach was to first evaluate the state of the science regarding the ability to quantify benefits to listed salmon and trout from habitat restoration actions in the LCRE in the 2009 project year, and then, if feasible, in subsequent project years to develop quantitative indices of habitat connectivity, early life history diversity, and survival. Based on the 2009 literature review, the following definitions are used in this study. Habitat connectivity is defined as a landscape descriptor concerning the ability of organisms to move among habitat patches, including the spatial arrangement of habitats (structural connectivity) and how the perception and behavior of salmon affect the potential for movement among habitats (functional connectivity). Life history is defined as the combination of traits exhibited by an organism throughout its life cycle, and for the purposes of this investigation, a life history strategy refers to the body size and temporal patterns of estuarine usage exhibited by migrating juvenile salmon. Survival is defined as the probability of fish remaining alive over a defined amount of space and/or time. The objectives of the 4-year study are as follows: (1) develop and test a quantitative index of juvenile salmon habitat connectivity in the LCRE incorporating structural, functional, and hydrologic components; (2) develop and test a quantitative index of the early life history diversity of juvenile salmon in the LCRE; (3) assess and, if feasible, develop and test a quantitative index of the survival benefits of tidal wetland habitat restoration (hydrologic reconnection) in the LCRE; and (4) synthesize the results of investigations into the indices for habitat connectivity, early life history diversity, and survival benefits.

  16. DPC loading feasibility study report

    SciTech Connect

    Dafoe, R.E.; Lopez, D.A.; Williams, K.L.

    1997-11-01

    Disposal of radioactive wastes now stored at the Idaho Chemical Processing Plant at the Idaho National Engineering and Environmental Laboratory is mandated under a ``Settlement Agreement`` between the Department of Energy and the State of Idaho. This study investigates the feasibility of using the Dry Transfer Cell facility to package waste into Dual Purpose Canisters for interim storage at the adjacent Dry Storage System comprised of an interim storage pad with NUHOMS{reg_sign} storage modules. The wastes would then be road-ready for eventual disposal in a permanent repository. The operating period for these activities is expected to be from 2015 to 2035.

  17. An Ecosystem-Based Restoration Plan with Emphasis on Salmonid Habitats in the Lower Columbia River and Estuary

    SciTech Connect

    Johnson, Gary E.; Thom, Ronald M.; Whiting, Allan H.; Sutherland, George B.; Berquam, Taunja J.; Ebberts, Blaine; Ricci, Nicole M.; Southard, John A.; Wilcox, Jessica D.

    2003-10-14

    The Bonneville Power Administration (BPA), in coordination with the U. S. Army Corps of Engineers (COE) and NOAA Fisheries, originated this project (BPA Project No. 2002-076; Contract No. DE-AC06-76RL01830, Release No. 652-24). Their intent was to develop a useful habitat restoration plan for the lower Columbia River and estuary to help guide restoration efforts and fulfill Reasonable and Prudent Alternative Action 159 of the 2000 National Marine Fisheries Service Biological Opinion on operation of the Federal Columbia River Power System. This document focuses on salmon habitat, although its ecosystem-based approach necessarily affects other species as well. Salmon habitat restoration is best undertaken within the context of other biota and physical processes using an ecosystem perspective. The anticipated audience for the plan includes entities responsible for, interested in, or affected by habitat restoration in the lower Columbia River and estuary. Timeframes to apply this plan extend from the immediate (2003-2004) to the near-term (2005-2006) to the long-term (2007 and beyond). We anticipate and encourage that the plan be revised as new knowledge and experience are attained. A team comprised of the Columbia River Estuary Study Taskforce (CREST), the Lower Columbia River Estuary Partnership (Estuary Partnership), and Pacific Northwest National Laboratory (PNNL) wrote this document. The BPA and the COE, as the responsible Action Agencies, provided technical oversight. The Estuary Partnership's Science Work Group, NOAA Fisheries Habitat Conservation Division, Northwest Power Planning Council (NPPC) staff, and state and tribal fisheries management agencies reviewed drafts. The Independent Scientific Advisory Board of the NPPC reviewed and commented on the 90% draft. Revisions were incorporated into the final draft document subsequently released for public review. Extensive efforts were made to ensure a sound technical and policy basis and to solicit input from all interested parties.

  18. Small estuary, big port - progress in the management of the Stour-Orwell Estuary system

    NASA Astrophysics Data System (ADS)

    Spearman, Jeremy; Baugh, John; Feates, Nigel; Dearnaley, Mike; Eccles, Dan

    2014-10-01

    Management of port development is increasingly challenging because of the competitive requirement for deeper channels and because of the need to preserve important coastal wetlands which function as both habitat and flood defence. This paper describes the management of the Stour/Orwell Estuary system, Eastern England, an estuary system which has experienced considerable development and morphological change. The estuary is internationally important for its wetland bird populations and the intertidal areas of the estuary system are protected under European legislation. It is also the location of the Port of Felixstowe. In 1998/2000 the approach channel to the Port of Felixstowe was deepened from -12.5 mCD to -14.5 mCD. This paper describes the effects of the approach channel deepening, the approach taken to identifying the potential impact to intertidal habitat resulting from the deepening, the sediment recycling implemented as mitigation to prevent increased loss of habitat and the subsequent response of the estuary system to this intervention.

  19. Geographic signatures of North American West Coast estuaries

    Microsoft Academic Search

    Robert Emmett; ROBERTO LLANSO ´; Jan Newton; Ron Thom; Michelle Hornberger; Cheryl Morgan; Colin Levings; Andrea Copping; Paul Fishman

    2000-01-01

    West Coast estuaries are geologically young and composed of a variety of geomorphological types. These estuaries range from\\u000a large fjords to shallow lagoons; from large to low freshwater flows. Natural hazards include E1 Niños, strong Pacific storms,\\u000a and active tectonic activity. West Coast estuaries support a wide range of living resources: five salmon species, harvestable\\u000a shellfish, waterfowl and marine birds,

  20. Modelling Pb and Cd dynamics in the Seine estuary

    Microsoft Academic Search

    B. Thouvenin; J. L. Gonzalez; J. F. Chiffoleau; B. Boutier; P. Le Hir

    2007-01-01

    The Seine estuary (France) is currently one of the world’s most contaminated estuaries, due in particular to its high cadmium\\u000a and lead content. Proper understanding of contaminant transfer, transformation and retention mechanisms throughout the estuary\\u000a and up to the adjacent marine zone require a range of studies involving data collections, experiments, and modeling tool.\\u000a A multivariable transport model (SiAM-3D) was

  1. Volume II, Chapter 3 Columbia River Estuary Tributaries

    E-print Network

    .......................................................................................................... 3-8 3.5.5 Substrate & Sediment into broad estuaries and then into Baker Bay. Their basins have a combination of sedimentary and volcanic

  2. Impact of climate change on Gironde Estuary

    NASA Astrophysics Data System (ADS)

    Laborie, Vanessya; Hissel, François; Sergent, Philippe

    2014-05-01

    Within the THESEUS European project, a simplified mathematical model for storm surge levels in the Bay of Biscay was adjusted on 10 events at Le Verdon using wind and pressure fields from CLM/SGA, so that the water levels at Le Verdon have the same statistic quantiles as observed tide records for the period [1960-2000]. The analysis of future storm surge levels shows a decrease in their quantiles at Le Verdon, whereas there is an increase of the quantiles of total water levels. This increase is smaller than the sea level rise and gets even smaller as one enters farther upstream in the estuary. A numerical model of the Gironde Estuary was then used to evaluate future water levels at 6 locations of the estuary from Le Verdon to Bordeaux and to assess the changes in the quantiles of water levels during the XXIst century using ONERC's pessimistic scenario for sea level rise (60 cm). The model was fed by several data sources : wind fields at Royan and Mérignac interpolated from the grid of the European Climatolologic Model CLM/SGA, a tide signal at Le Verdon, the discharges of Garonne (at La Réole), the Dordogne (at Pessac) and Isle (at Libourne). A series of flood maps for different return periods between 2 and 100 years and for four time periods ([1960-1999], [2010-2039], [2040-2069] and [2070-2099]) have been built for the region of Bordeaux. Quantiles of water levels in the floodplain have also been calculated. The impact of climate change on the evolution of flooded areas in the Gironde Estuary and on quantiles of water levels in the floodplain mainly depends on the sea level rise. Areas which are not currently flooded for low return periods will be inundated in 2100. The influence of river discharges and dike breaching should also be taken into account for more accurate results.

  3. Geomorphological study of sundarban deltaic estuary

    Microsoft Academic Search

    Dipnarayan Ganguly; Anirban Mukhopadhyay; Rahul Krishna Pandey; Debasish Mitra

    2006-01-01

    Summary  Study of landforms in Sundarbans deltaic estuary is necessary in regular basis due to its importance and impact on ecology,\\u000a climate and economy. Remote sensing has proved as an important tool to study this. Multi-temporal satellite data helps to\\u000a delineate the various geomorphic classes in different time domain and also provide inputs to study the coastal erosion and\\u000a accretion. Finer

  4. Tidal exchange between a freshwater tidal marsh and an impacted estuary: the Scheldt estuary, Belgium

    NASA Astrophysics Data System (ADS)

    Van Damme, Stefan; Frank, Dehairs; Micky, Tackx; Olivier, Beauchard; Eric, Struyf; Britta, Gribsholt; Oswald, Van Cleemput; Patrick, Meire

    2009-11-01

    Tidal marsh exchange studies are relatively simple tools to investigate the interaction between tidal marshes and estuaries. They have mostly been confined to only a few elements and to saltwater or brackish systems. This study presents mass-balance results of an integrated one year campaign in a freshwater tidal marsh along the Scheldt estuary (Belgium), covering oxygen, nutrients (N, P and Si), carbon, chlorophyll, suspended matter, chloride and sulfate. The role of seepage from the marsh was also investigated. A ranking between the parameters revealed that oxygenation was the strongest effect of the marsh on the estuarine water. Particulate parameters showed overall import. Export of dissolved silica (DSi) was more important than exchange of any other nutrient form. Export of DSi and import of total dissolved nitrogen (DIN) nevertheless contributed about equally to the increase of the Si:N ratio in the seepage water. The marsh had a counteracting effect on the long term trend of nutrient ratios in the estuary.

  5. Engineering Engineering

    E-print Network

    Maroncelli, Mark

    Engineering Engineering Technology & A T P E N N S T A T E 2 0 1 0 ­ 2 0 1 1 #12;2 Join us at penn state! Since 1896, Penn State has been a leader in engineering and engineering technology education varieties of engineering and engineering technology majors found anywhere in the United States. This means

  6. Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River and Estuary in 2009

    SciTech Connect

    McMichael, Geoffrey A.; Harnish, Ryan A.; Bellgraph, Brian J.; Carter, Jessica A.; Ham, Kenneth D.; Titzler, P. Scott; Hughes, Michael S.

    2010-08-01

    The study reported herein was funded as part of the Anadromous Fish Evaluation Program, which is managed by the U.S. Army Corps of Engineers (USACE). The Anadromous Fish Evaluation Program study code is EST P 02 01: A Study of Salmonid Survival and Behavior through the Columbia River Estuary Using Acoustic Tags. The study was conducted by the Pacific Northwest National Laboratory (PNNL) and National Oceanic and Atmospheric Administration (NOAA) Fisheries for the USACE Portland District. Estimated survival of acoustic-tagged juvenile Chinook salmon and steelhead through the lower Columbia River and estuary in 2009 was lowest in the final 50 km of the estuary. Probability of survival was relatively high (>0.90) for yearling and subyearling Chinook salmon from the Bonneville Dam forebay (rkm 236) to Three-tree Point (rkm 49.6). Survival of juvenile Chinook salmon declined sharply through the lower 50 km of the estuary. Acoustic-tagged steelhead smolts did not survive as well as juvenile Chinook salmon between Bonneville Dam and the mouth of the Columbia River. Steelhead survival began to decline farther upstream (at rkm 86) relative to that of the Chinook salmon stocks. Subyearling Chinook salmon survival decreased markedly as the season progressed. It remains to be determined whether later migrating subyearling Chinook salmon are suffering increasing mortality as the season progresses or whether some portion of the apparent loss is due to fish extending their freshwater residence. This study provided the first glimpse into what promises to be a very informative way to learn more about how juvenile salmonid passage experiences through the FCRPS may influence their subsequent survival after passing Bonneville Dam. New information regarding the influence of migration pathway through the lower 50 km of the Columbia River estuary on probability of survival of juvenile salmonids, combined with increased understanding regarding the foraging distances and time periods of avian predators should prove useful in developing or assessing management actions to reduce losses of juvenile salmonid smolts that attempt to pass through the estuary on their seaward migration.

  7. Flow Liner Slot Edge Replication Feasibility Study

    NASA Technical Reports Server (NTRS)

    Newman, John A.; Willard, Scott A.; Smith, Stephen W.; Piascik, Robert S.

    2006-01-01

    Surface replication has been proposed as a method for crack detection in space shuttle main engine flowliner slots. The results of a feasibility study show that examination of surface replicas with a scanning electron microscope can result in the detection of cracks as small as 0.005 inch, and surface flaws as small as 0.001 inch, for the flowliner material.

  8. FEASIBILITY OF INTERSTELLAR TRAVEL

    Microsoft Academic Search

    D. F. Spencer; L. D. Jaffe

    1962-01-01

    The feasibility of interstellar flight is discussed. Mathematical ; equations for single-stage and multistage rocket propulsion are developed, ; velocity data and transit times are presented, and mass ratios required for ; fission and fusion rockets are given. The conclusions indicate that interstellar ; travel is theoretically feasible by utilizing known staged nuclear-energy systems. ; (auth);

  9. Feasibility and Cost Analysis.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Education, Raleigh.

    North Carolina school districts thinking about building new educational facilities are legislatively required to conduct an analysis that compares the costs and feasibility of building the new building versus renovating an old building. This document contains the cost and feasibility forms suggested for use in this analysis. The forms provide a…

  10. Freshwater, tidal and wave influences on a small estuary

    NASA Astrophysics Data System (ADS)

    Uncles, R. J.; Stephens, J. A.; Harris, C.

    2014-10-01

    Observations are presented of water levels, currents, salinity, turbidity, sediment grain sizes and sediment transport in the Devonshire Avon Estuary, UK, in order to improve knowledge of freshwater, wave and tidal influences on small, strongly tidal ría estuaries. A large reduction in tidal range occurred progressing from the coastal zone to the upper estuary that was mainly a consequence of rising bed and river water levels. The spring-neap cycle also had an influence on the reduction in tidal range along the length of the estuary. Surface gravity waves were completely dissipated propagating into the estuarine channel from the coastal zone, and despite strong wave-induced resuspension, suspended sediment was not transported into the lower estuary in observable amounts during the ensuing flood tide, indicating that the wave-suspended material was too coarse to remain in suspension once transported away from the surf zone. Turbidity in the lower estuary was relatively low during low runoff summer conditions and had largest values over low water, when turbid waters from farther up-estuary had been transported there. Strong resuspension events occurred at peak currents in the upper estuary during summer, reflecting the presence of finer-grained sediment sources. Turbidity was similar but greater in the lower estuary during high runoff winter conditions and strong resuspension occurred at peak currents, indicating an easily erodible, nearby sediment source, due to down-estuary movement and relocation of finer sediment over the winter. A large shoal in the lower estuary exhibited a consistent pattern of accretion/erosion during the high runoff months of late autumn and winter to spring that also was qualitatively consistent with sediment transport modelling and implied: (a), erosion from the up-estuary limit of the shoal with (b), down-estuary bed-load and suspended-load transport that accreted the centre and down-estuary limit of the shoal until (c), a diminished supply led to erosion via continued down-estuary transport from the shoal centre.

  11. Role and Value of Nitrogen Regulation Provided by Oysters (Crassostrea virginica) in the Mission-Aransas Estuary, Texas, USA

    PubMed Central

    Beseres Pollack, Jennifer; Yoskowitz, David; Kim, Hae-Cheol; Montagna, Paul A.

    2013-01-01

    Suspension-feeding activities of oysters impart a potentially significant benefit to estuarine ecosystems via reduction of water column nutrients, plankton and seston biomass, and primary productivity which can have a significant impact on human well-being. This study considered nitrogen regulation by eastern oysters Crassostrea virginica in the Mission-Aransas Estuary, Texas, USA, as a function of denitrification, burial, and physical transport from the system via harvest. Oyster reefs were estimated to remove 502.5 kg N km?2 through denitrification of biodeposits and 251.3 kg N km?2 in burial of biodeposits to sediments. Nitrogen is also physically transported out of the estuary via harvest of oysters. Commercial harvest of oysters in the Mission-Aransas Estuary can remove approximately 21,665 kg N per year via physical transport from the system. We developed a transferable method to value the service of nitrogen regulation by oysters, where the potential cost equivalent value of nitrogen regulation is quantified via cost estimates for a constructed biological nutrient removal (BNR) supplement to a wastewater treatment plant. The potential annual engineered cost equivalent of the service of nitrogen regulation and removal provided by reefs in the Mission-Aransas Estuary is $293,993 yr?1. Monetizing ecosystem services can help increase awareness at the stakeholder level of the importance of oysters beyond commercial fishery values alone. PMID:23762341

  12. The feasibility of deep well injection for brine disposal

    E-print Network

    Spongberg, Martin Edward

    1994-01-01

    A generalized methodology for evaluating the technical feasibility of projects involving the disposal of waste brine by injection into deep saline aquifers is developed, primarily from the hydrology and petroleum engineering literature. Data...

  13. Tide-driven fluid mud transport in the Ems estuary

    NASA Astrophysics Data System (ADS)

    Becker, Marius; Maushake, Christian; Winter, Christian

    2014-05-01

    The Ems estuary, located at the border between The Netherlands and Germany, experienced a significant change of the hydrodynamic regime during the past decades, as a result of extensive river engineering. With the net sediment transport now being flood-oriented, suspended sediment concentrations have increased dramatically, inducing siltation and formation of fluid mud layers, which, in turn, influence hydraulic flow properties, such as turbulence and the apparent bed roughness. Here, the process-based understanding of fluid mud is essential to model and predict mud accumulation, not only regarding the anthropogenic impact, but also in view of the expected changes of environmental boundary conditions, i.e., sea level rise. In the recent past, substantial progress has been made concerning the understanding of estuarine circulation and influence of tidal asymmetry on upstream sediment accumulation. While associated sediment transport formulations have been implemented in the framework of numerical modelling systems, in-situ data of fluid mud are scarce. This study presents results on tide-driven fluid mud dynamics, measured during four tidal cycles aside the navigation channel in the Ems estuary. Lutoclines, i.e., strong vertical density gradients, were detected by sediment echo sounder (SES). Acoustic Doppler current profiles (ADCP) of different acoustic frequencies were used to determine hydrodynamic parameters and the vertical distribution of suspended sediment concentrations in the upper part of the water column. These continuous profiling measurements were complemented by CTD, ADV, and OBS casts. SES and ADCP profiles show cycles of fluid mud entrainment during accelerating flow, and subsequent settling, and the reformation of a lutocline during decelerating flow and slack water. Significant differences are revealed between flood and ebb phase. Highest entrainment rates are measured at the beginning of the flood phase, associated with strong current shear and rapid vertical mixing, inducing the highest instantaneous suspended sediment flux measured during the tidal cycle. During decelerating flood currents a lutocline is again established at a certain distance above the consolidated river bed. During slack water after the flood phase the concentration gradient increases and the thickness of the fluid mud layer below is constant, also during a significant part of the ebb phase. As water depth decreases during ebb, entrainment occurs only at the upper part of the fluid mud layer. The suspended sediment flux is low compared to the flood phase. These observations are further elaborated using turbulence parameters obtained from ADV and ADCP, explaining the difference between ebb and flood concerning the vertical location of the maximum concentration gradient. This study is funded through DFG-Research Center / Excellence Cluster "The Ocean in the Earth System". The Senckenberg Institute and the Federal Waterways Engineering and Research Institute are acknowledged for technical support.

  14. LIMNETIC LARVAL FISH OF THE MAUMEE AND SANDUSKY RIVER ESTUARIES

    EPA Science Inventory

    A total of 17 taxa were collected in the Maumee River estuary during sampling periods in 1975, 1976, and 1977. A total of 11 taxa were collected from the Sandusky River estuary in 1976. Gizzard shad/alewife, Dorosoma cepedianum/Alosa pseudoharengus, white bass/white perch, Morone...

  15. Contaminant Modeling in San Francisco Bay: Lessons from Other Estuaries

    E-print Network

    Contaminant Modeling in San Francisco Bay: Lessons from Other Estuaries Dr. Joel Baker Director, UW chemical contaminants in estuaries · Approaches and common traits of estuarine contaminant models · What is missing? · Final thoughts #12;Outline · Utility and challenges of modeling chemical contaminants

  16. YAQUINA BAY AND BEYOND: WHAT SHAPE ARE OUR ESTUARIES IN?

    EPA Science Inventory

    The great natural beauty of Oregon's estuaries gives an impression of systems that are far less altered than those in other areas of the US. However, over the years, Yaquina Bay and other western estuaries have been variously affected by habitat loss and alteration, over harvest...

  17. Nitrogen Source and Loading Data for EPA Estuary Data Mapper

    EPA Science Inventory

    Nitrogen source and loading data have been compiled and aggregated at the scale of estuaries and associated watersheds of the conterminous United States, using the spatial framework in EPA's Estuary Data Mapper (EDM) to provide system boundaries. Original sources of data include...

  18. PECONIC ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN

    EPA Science Inventory

    The Peconic Estuary, situated between the North and South Forks of eastern Long Island, New York, consists of more than 100 distinct bays, harbors, embayments, and tributaries. The area surrounding the Peconic Estuary's watershed is rich in rolling farmland, scenic beaches and cr...

  19. LOWER COLUMBIA RIVER ESTUARY PROGRAM COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN

    EPA Science Inventory

    An estuary is the area where the fresh water of a river meets the salt water of an ocean. In the Columbia River system, this occurs in the lower 46 river miles. In an estuary, the river has a direct, natural connection with the open sea. This transition from fresh to salt water c...

  20. WATER QUALITY MODELING IN THE RIO CHONE ESTUARY

    EPA Science Inventory

    Water quality in the Rio Chone Estuary, a seasonally inverse, tropical estuary, in Ecuador was characterized by modeling the distribution of biochemical oxygen demand (BOD) and dissolved inorganic nitrogen (DIN) within the water column. These two variables are modeled using modif...

  1. Macroalgae, pore water sulfides and eelgrass in Yaquina estuary, Oregon

    EPA Science Inventory

    The hypothesis that relatively high nutrients in estuaries of the Pacific Northwest (PNW) can lead to eutrophication and degradation of critical eelgrass habitat was examined. Yaquina estuary was surveyed for cover and above-ground biomass of benthic macroalgae (Ulva spp.) and n...

  2. PECONIC ESTUARY: RECREATIONAL AND RESOURCE ECONOMIC VALUES FOR THE PECONIC ESTUARY SYSTEM

    EPA Science Inventory

    The environmental and natural resources ("natural assets") of the Peconic Estuary System--the bay waters, beaches, wetlands, ecosystems, habitats, and parks and watershed lands--provide many services to the public. Outdoor recreation, scenic views, and the productivity of wetland...

  3. Approaches for Development of Nutrient Criteria in Oregon Estuaries With a Focus on Tillamook Estuary

    EPA Science Inventory

    Development of nutrient criteria for all water body types of the US remains a top priority for EPA. Estuaries in the Pacific Northwest receive nutrients from both the watershed and the coastal ocean, and thus are particularly complex systems in which to establish water quality c...

  4. The Oncor Geodatabase for the Columbia Estuary Ecosystem Restoration Program: Annual Report, 2012

    SciTech Connect

    Coleman, Andre M.; Johnson, Gary E.; Borde, Amy B.; Diefenderfer, Heida L.; Sather, Nichole K.; Seiple, Timothy E.; Serkowski, John A.

    2013-11-10

    Pacific Northwest National Laboratory (PNNL) conducted this project for the U.S. Army Corps of Engineers, Portland District (Corps). The purpose of the project is to develop a geospatial, web-accessible database (called “Oncor”) for action effectiveness and related data from monitoring and research efforts for the Columbia Estuary Ecosystem Restoration Program (CEERP). The intent is for the Oncor database to enable synthesis and evaluation, the results of which can then be applied in subsequent CEERP decision-making. This is the first annual report in what is expected to be a 3- to 4-year project, which commenced on February 14, 2012.

  5. Salmon Life Histories, Habitats, and Food Webs in the Columbia River Estuary

    E-print Network

    Salmon Life Histories, Habitats, and Food Webs in the Columbia River Estuary Daniel J. Bottom NOAA management efforts in the Columbia River estuary on behalf of salmon: (1) the estuary is irrelevant to conservation because fresh water conditions limit salmon production; and (2) the estuary is a threat

  6. A hybrid approach to estimate chromophoric dissolved organic matter in turbid estuaries from

    E-print Network

    Meyers, Steven D.

    A hybrid approach to estimate chromophoric dissolved organic matter in turbid estuaries from to derive CDOM absorption coefficient at 443 nm (ag(443), m-1 ) in a turbid estuary (Tampa Bay) from MODIS discharge. Testing of the approach over another turbid estuary (Chesapeake Bay, the largest estuary in the U

  7. PECONIC ESTUARY: AN INVENTORY OF SUBMERGED AQUATIC VEGETATION AND HARDENED SHORELINES FOR THE PECONIC ESTUARY, NEW YORK

    EPA Science Inventory

    Executive Summary The Peconic Estuary Program (PEP) is interested in the extent of eelgrass and other submerged aquatic vegetation and in documenting changes in the shorelines of the Peconic Estuary. The Suffolk County Department of Health Services' Office of Ecology provided fun...

  8. Delaware Estuary situation reports. Emergency response: How do emergency management officials address disasters in the Delaware Estuary

    Microsoft Academic Search

    Sylves

    1991-01-01

    From hurricanes and other natural threats to oil spills and other manmade emergencies, the Delaware Estuary has experienced a variety of disasters over the years. The toll that these events take on the estuary and those who live on its shores depends largely upon the degree of emergency preparedness, speed of response, and effectiveness of recovery operations. In Emergency Response:

  9. 14-plex Feasibility Report

    SciTech Connect

    Kotongan, Victoria Hazel [Native Village of Unalakleet

    2013-06-21

    The Native Village of Unalakleet project was a feasibility study for a retrofit of a “tribally owned” three story, 14 apartment complex located in Unalakleet, Alaska. The program objective and overall goal was to create a plan for retrofitting to include current appraised value and comparable costs of new construction to determine genuine feasibility as low-income multi-family housing for tribal members.

  10. Change in Land Cover along the Lower Columbia River Estuary as Determined from Landsat Thematic Mapper (TM) Imagery, Technical Report 2003.

    SciTech Connect

    Garono, Ralph; Anderson, Becci; Robinson, Rob

    2003-10-01

    The Lower Columbia River Estuary Management Plan (Jerrick, 1991) recognizes the positive relationship between the conservation of fish and wildlife habitat, and sustaining their populations. An important component of fish and wildlife conservation and management is the identification of habitats, trends in habitat change, and delineation of habitat for preservation, restoration or enhancement. Alterations to the environment, such as hydropower generation, dredging, forestry, agriculture, channel alteration, diking, bank stabilization and floodplain development, have dramatically altered both the type and distribution of habitats along the Columbia River Estuary (CRE) and its floodplain. Along the Columbia River, tidally influenced habitats occur from the river mouth to the Bonneville Dam, a distance of 230 km. If we are to effectively manage the natural resources of the Columbia River ecosystem, there is a need to understand how habitats have changed because fish and wildlife populations are known to respond to changes in habitat quality and distribution. The goal of this study was to measure the amount and type of change of CRE land cover from 1992 to 2000. We performed a change analysis on two spatial data sets describing land cover along the lower portion of the estuary (Fig. 1). The 1992 data set was created by the NOAA Coastal Remote Sensing, Coastal Change Analysis Program (C-CAP) in cooperation with Columbia River Estuary Study Task Force (CREST), the National Marine Fisheries Service (NMFS) Point Adams Field Station, and State of Washington Department of Natural Resources (DNR). The 2000 data set was produced by Earth Design Consultants, Inc. (EDC) and the Wetland Ecosystem Team (WET: University of Washington) as part of a larger Lower Columbia River Estuary Partnership (Estuary Partnership) habitat mapping study. Although the image classification methodologies used to create the data sets differed, both data sets were produced by classifying Landsat Thematic Mapper (TM) satellite imagery, making it feasible to assess land cover changes between 1992 and 2000.

  11. MAIA Estuaries 1997-98 Data

    NSDL National Science Digital Library

    The Mid Atlantic Integrated Assessment program (MAIA) of the Environmental Protection Agency (EPA) has released these estuaries data for 1997-98. Data and Metadata may be viewed or downloaded (text or .pdf) for the following variables: Sampling Station Location Data, Station Visit Data, Water Quality Physical Measurements, Water Quality- Nutrients Data, Sediment Grain Size Data, Sediment Toxicity Data, Sediment Chemistry Data, Benthic Community Grain Size Data, Benthic Abundance Data, Benthic Biomass Data, Benthic Community Summary Data, Chemical Analyte Code Table, and Benthic Taxon Code Table.

  12. [Vulnerability assessment on the coastal wetlands in the Yangtze Estuary under sea-level rise].

    PubMed

    Cui, Li-Fang; Wang, Ning; Ge, Zhen-Ming; Zhang, Li-Quan

    2014-02-01

    To study the response of coastal wetlands to climate change, assess the impacts of climate change on the coastal wetlands and formulate feasible and practical mitigation strategies are the important prerequisite for securing coastal ecosystems. In this paper, the possible impacts of sea level rise caused by climate change on the coastal wetlands in the Yangtze Estuary were analyzed by the Source-Pathway-Receptor-Consequence (SPRC) model and IPCC definition on the vulnerability. An indicator system for vulnerability assessment was established, in which sea-level rise rate, subsidence rate, habitat elevation, inundation threshold of habitat and sedimentation rate were selected as the key indicators. A quantitatively spatial assessment method based on the GIS platform was established by quantifying each indicator, calculating the vulnerability index and grading the vulnerability index for the assessment of coastal wetlands in the Yangtze Estuary under the scenarios of sea-level rise. The vulnerability assessments on the coastal wetlands in the Yangtze Estuary in 2030 and 2050 were performed under two sea-level rise scenarios (the present sea-level rise trend over recent 30 years and IPCC A1F1 scenario). The results showed that with the projection in 2030 under the present trend of sea-level rise (0.26 cm x a(-1)), 6.6% and 0.1% of the coastal wetlands were in the low and moderate vulnerabilities, respectively; and in 2050, 9.8% and 0.2% of the coastal wetlands were in low and moderate vulnerabilities, respectively. With the projection in 2030 under the A1F1 scenario (0.59 cm x a(-1)), 9.0% and 0.1% of the coastal wetlands were in the low and moderate vulnerabilities, respectively; and in 2050, 9.5%, 1.0% and 0.3% of the coastal wetlands were in the low, moderate and high vulnerabilities, respectively. PMID:24830257

  13. Denitrification in the river estuaries of the northern Baltic Sea.

    PubMed

    Silvennoinen, Hanna; Hietanen, Susanna; Liikanen, Anu; Stange, C Florian; Russow, Rolf; Kuparinen, Jorma; Martikainen, Pertti J

    2007-04-01

    Estuaries have been suggested to have an important role in reducing the nitrogen load transported to the sea. We measured denitrification rates in six estuaries of the northern Baltic Sea. Four of them were river mouths in the Bothnian Bay (northern Gulf of Bothnia), and two were estuary bays, one in the Archipelago Sea (southern Gulf of Bothnia) and the other in the Gulf of Finland. Denitrification rates in the four river mouths varied between 330 and 905 micromol N m(-2) d(-1). The estuary bays at the Archipelago Sea and the Gulf of Bothnia had denitrification rates from 90 micromol N m(-2) d(-1) to 910 micromol N m(-2) d(-1) and from 230 micromol N m(-2) d(-1) to 320 micromol N m(-2) d(-1), respectively. Denitrification removed 3.6-9.0% of the total nitrogen loading in the river mouths and in the estuary bay in the Gulf of Finland, where the residence times were short. In the estuary bay with a long residence time, in the Archipelago Sea, up to 4.5% of nitrate loading and 19% of nitrogen loading were removed before entering the sea. According to our results, the sediments of the fast-flowing rivers and the estuary areas with short residence times have a limited capacity to reduce the nitrogen load to the Baltic Sea. PMID:17520925

  14. Tidal bore dynamics in funnel-shaped estuaries

    NASA Astrophysics Data System (ADS)

    Bonneton, P.; Bonneton, N.; Parisot, J.-P.; Castelle, B.

    2015-02-01

    The formation and dynamics of tidal bores in funnel-shaped estuaries is investigated from both a global tidal wave scaling analysis and new quantitative field observations. We show that tidal bore occurrence in convergent estuaries can be estimated from a dimensionless scaling parameter characterizing the relative intensity of nonlinear friction versus local inertia in the momentum equation. A detailed analysis of tidal bore formation and secondary wave structure is presented from a unique long-term database (observations of more than 200 tides) acquired during four campaigns in the two main French tidal-bore estuaries: the Seine and Gironde/Garonne estuaries. We describe the effect of freshwater discharge on the global tidal wave transformation at the estuarine scale and on local tidal bore occurrence in the upper estuary. Our field data suggest that the tidal bore intensity is mainly governed by the dimensionless tidal range, which characterizes the local tidal wave nonlinearity. We also show that the secondary wavefield associated with tidal bore propagating in natural estuaries differs significantly from those associated to undular bores in rectangular channels. In particular, we observe an abrupt decrease of the whelp steepness when the Froude number goes below 1.1. This secondary field transition can explain why tidal bore occurrence in worldwide estuaries is certainly underestimated.

  15. Mercury distribution in Douro estuary (Portugal).

    PubMed

    Ramalhosa, E; Pereira, E; Vale, C; Válega, M; Monterroso, P; Duarte, A C

    2005-11-01

    Determinations of dissolved reactive and total dissolved mercury, particulate and sedimentary mercury, dissolved organic carbon (DOC), particulate organic carbon (POC) and suspended particulate matter (SPM) have been made in the estuary of river Douro, in northern Portugal. The estuary was stratified by salinity along most of its length, it had low concentrations of SPM, typically <20 mg dm(-3), and concentrations of DOC in the range <1.0-1.8 mg dm(-3). The surface waters had a maximum dissolved concentration of reactive mercury of about 10 ng dm(-3), whereas for the more saline bottom waters it was about 65 ng dm(-3). The surface waters had maximum concentrations of total suspended particulate mercury of approximately 7 microg g(-1) and the bottom waters were always <1 microg g(-1). Concentrations of mercury in sediments was low and in the range from 0.06 to 0.18 microg g(-1). The transport of mercury in surface waters was mainly associated with organic-rich particulate matter, while in bottom waters the dissolved phase transport of mercury is more important. Lower particulate organic matter, formation of chlorocomplexes in more saline waters and eventually the presence of colloids appear to explain the difference of mercury partitioning in Douro estuarine waters. PMID:15893331

  16. Sediment Transport Processes In River Dominated Sub-Tropical Estuaries

    NASA Astrophysics Data System (ADS)

    DAquino, Carla; Schettini, Carlos

    2014-05-01

    The objective of this study is to present a comparative assessment of the largest three river dominated estuaries in the southern coast of the state of Santa Catarina, Brazil (Tubarão, Araranguá and Mampituba estuaries). The study was focused on mechanisms of transport of suspended sediments influenced by its morphologic and hydrodynamics characteristics. As shown in D'Aquino et al (2011), these estuaries share common attributes (climate and tides) and follow the basic conceptual model of fine sediment transport (presented by Toldo & Schettini (2006). However, each one has its own particularities regarding the geographical setting, land use, hypsometry, outfall, etc. The methodology used to the field measurements was the same for all estuaries, aiming at measuring the currents, water level, salinity, temperature and turbidity near the outfall for at least two complete tidal cycles (~25 hours). All the campaigns were carried on under syzygya tide conditions. During the sample collecting period, a longitudinal profile was conducted in each estuary, through acquisitions of salinity and temperature of the water column in every kilometer. In the Tubarão and Araranguá rivers estuaries, the concentration of suspended particulate matter (SPM) is mostly influenced by the periods of incoming tide, flood currents. In the Mampituba river estuary, the flocculation process was observed during the encounter of fresh and salt water in every tide entrance. It was possible to observe that the Araranguá river estuary, in what concerns the bottom SPM, responds to the variation of salinity and currents along the bottom. The Tubarão estuary presents a relation between the salinity and the bottom currents. In the Mampituba estuary no relevant correlation was found between the SPM, the salinity, and the bottom currents. Those aspects demonstrate that even sharing some characteristics there are significant differences among these estuaries. In addition, as a result of the comparative study, an analytical model was proposed that correlates the fluvial discharge, salt wedge, and SPM. This model might represent a tool to encourage discussions and help the scientific exploration of the estuaries in the south of Santa Catarina.

  17. Development of a Hydrodynamic Model for Skagit River Estuary for Estuarine Restoration Feasibility Assessment

    SciTech Connect

    Yang, Zhaoqing; Liu, Hedong; Khangaonkar, Tarang P.

    2006-08-03

    The Skagit River is the largest river in the Puget Sound estuarine system. It discharges about 39% of total sediment and more than 20% of freshwater into Puget Sound. The Skagit River delta provides rich estuarine and freshwater habitats for salmon and many other wildlife species. Over the past 150 years, economic development in the Skagit River delta has resulted in significant losses of wildlife habitat, particularly due to construction of dikes. Diked portion of the delta is known as Fir Island where irrigation practices for agriculture land over the last century has resulted in land subsidence. This has also caused reduced efficiency of drainage network and impeded fish passages through the area. In this study, a three-dimensional tidal circulation model was developed for the Skagit River delta to assist estuarine restoration in the Fir Island area. The hydrodynamic model used in the study is the Finite Volume Coastal Ocean Model (FVCOM). The hydrodynamic model was calibrated using field data collected from the study area specifically for the model development. Wetting and drying processes in the estuarine delta are simulated in the hydrodynamic model. The calibrated model was applied to simulate different restoration alternatives and provide guidance for estuarine restoration and management. Specifically, the model was used to help select and design configurations that would improve the supply of sediment and freshwater to the mudflats and tidal marsh areas outside of diked regions and then improve the estuarine habitats for salmon migration.

  18. The Deschutes Estuary Restoration Feasibility Study: development of a process-based morphological model

    E-print Network

    transport after dam removal will also be modeled. Key components of the model include tidal currents. Several restoration solutions have been proposed, including removal of the dam and widening the opening Continual sediment accumulation in Capitol Lake since the damming of the Deschutes River in 1951 has altered

  19. Multi-Scale Action Effectiveness Research in the Lower Columbia River and Estuary, 2011 - FINAL ANNUAL REPORT

    SciTech Connect

    Sather, Nichole K.; Storch, Adam; Johnson, Gary E.; Teel, D. J.; Skalski, J. R.; Bryson, Amanda J.; Kaufmann, Ronald M.; Woodruff, Dana L.; Blaine, Jennifer; Kuligowski, D. R.; Kropp, Roy K.; Dawley, Earl M.

    2012-05-31

    The study reported here was conducted by researchers at Pacific Northwest National Laboratory (PNNL), the Oregon Department of Fish and Wildlife (ODFW), the University of Washington (UW), and the National Marine Fisheries Service (NMFS) for the U.S. Army Corps of Engineers, Portland District (USACE). This research project was initiated in 2007 by the Bonneville Power Administration to investigate critical uncertainties regarding juvenile salmon ecology in shallow tidal freshwater habitats of the lower Columbia River. However, as part of the Washington Memorandum of Agreement, the project was transferred to the USACE in 2010. In transferring from BPA to the USACE, the focus of the tidal freshwater research project shifted from fundamental ecology toward the effectiveness of restoration in the Lower Columbia River and estuary (LCRE). The research is conducted within the Action Agencies Columbia Estuary Ecosystem Restoration Program (CEERP). Data reported herein spans the time period May 2010 to September 2011.

  20. Northern New Mexico regional airport market feasibility

    SciTech Connect

    Drake, R.H.; Williams, D.S.

    1998-06-01

    This report is about the market for airline travel in northern New Mexico. Interest in developing a northern New Mexico regional airport has periodically surfaced for a number of years. The New Mexico State Legislature passed a memorial during the 1998 Second Session calling for the conduct of a study to determine the feasibility of building a new regional airport in NNM. This report is a study of the passenger market feasibility of such an airport. In addition to commercial passenger market feasibility, there are other feasibility issues dealing with siting, environmental impact, noise, economic impact, intermodal transportation integration, region-wide transportation services, airport engineering requirements, and others. These other feasibility issues are not analyzed in any depth in this report although none were discovered to be show-stoppers as a by-product of the authors doing research on the passenger market itself. Preceding the need for a detailed study of these other issues is the determination of the basic market need for an airport with regular commercial airline service in the first place. This report is restricted to an in-depth look at the market for commercial passenger air service in NNM. 20 figs., 8 tabs.

  1. DOWNSTREAM MIGRATION OF SALMONID SMOLTS IN OREGON RIVERS AND ESTUARIES

    EPA Science Inventory

    Migratory fish passage is an important designated use for many Oregon estuaries. Acoustic transmitters were implanted in coho smolts in 2004 and 2006 to evaluate how estuarine habitat, and habitat loss, might affect population health. Acoustic receivers that identified individu...

  2. MAPPING BURROWING SHRIMP AND SEAGRASS IN YAQUINA ESTUARY

    EPA Science Inventory

    Burrowing shrimp and seagrasses create extensive intertidal and shallow subtidal habitats within Pacific NW estuaries. Maps of their populations are useful to inform estuarine managers of locations that deserve special consideration for conservation, and to inform oyster farmers...

  3. Credit: Michael Anderson. NOAA Selects St. Louis River Estuary as

    E-print Network

    focus on fish and wildlife habitat rehabilitation and restoration, along with identifying non estuary include: · addressing loss of fish and wildlife habitat through the funding of targeted and wildlife populatio

  4. Evaluating Causes of Ecological Impairments in the Estuaries of Ukraine

    EPA Science Inventory

    Ukrainian estuaries have not undergone a systematic evaluation of the causes of ecological impairments caused by anthropogenic contamination. The objective of this evaluation is to use recently developed diagnostic tools to determine the causes of benthic ecological impairments. ...

  5. CASCO BAY ESTUARY PROJECT TRIENNIAL IMPLEMENTATION REVIEW MARCH, 2004

    EPA Science Inventory

    The Casco Bay Estuary Project has seven primary goals/priorities which include: minimize pollutant loading from stormwater; open and protect shellfish beds; protect and restore habitat; reduce toxic pollution; promote responsible stewardship; sustain and promote the continued eff...

  6. Annual cycle of hypoxia off the Changjiang (Yangtze River) Estuary.

    PubMed

    Wang, Baodong; Wei, Qinsheng; Chen, Jianfang; Xie, Linping

    2012-06-01

    The annual cycle of hypoxia off the Changjiang Estuary, China, was assessed from data acquired during nine cruises in 2006-2007. Hypoxia began to develop in late spring and early summer, reached its maximum in August, weakened in the autumn and finally disappeared in the winter. Hypoxia first developed south-east of the Changjiang Estuary in June, appeared in the east and north-east in July, and spread both south and north of the Changjiang Estuary in August. By September, it had started to recede in the north-east, and had dissipated in the southern part of the studied area by winter. The geographical displacement of the hypoxic zone was controlled by both seasonal changes in regional water column stratification and variations of the northward extension of the Taiwan Warm Current toward the Changjiang Estuary. PMID:22240466

  7. LOUISIANIAN PROVINCE DEMONSTRATION REPORT - EMAP-ESTUARIES: 1991

    EPA Science Inventory

    This report summarizes the Louisianian Demonstration Project conducted by the Estuaries Resource Group of the Environmental Monitoring and Assessment Program (EMAP), a national program initiated by EPA to integrate efforts of governmental agencies in evaluations of status and tre...

  8. Mixing processes and hydraulic control in a highly stratified estuary

    E-print Network

    MacDonald, Daniel George, 1970-

    2003-01-01

    This thesis utilizes field data from the Fraser River Estuary, a highly stratified system located in southwestern British Columbia, Canada, to investigate the nature of mixing processes in a highly stratified environment, ...

  9. NEKTON-HABITAT ASSOCIATIONS IN A PACIFIC NORTHWEST (USA) ESTUARY

    EPA Science Inventory

    Nekton-habitat associations were determined in Yaquina Bay, Oregon, United States, using a stratified-by-habitat, random, estuary-wide sampling design. Three habitats (intertidal eelgrass [Zostera marina], mud shrimp [Upogebia pugettensis], and ghost shrimp [Neotrypaea californie...

  10. oceanservice.noaa.gov/education 1 ESTUARY SUBJECT REVIEW

    E-print Network

    -shaped deposits of sediment at the mouth of a river. 27. __________ estuaries are formed when the earth's tectonic plates run into or fold-up underneath each other. 28. __________ are steep-walled river valleys created

  11. A PROBABILISTIC SURVEY OF SEDIMENT TOXICITY IN WEST COAST ESTUARIES

    EPA Science Inventory

    A probabalistic survey of coastal condition assessment was conducted in 1999 by participants in US EPA's Environmental Monitoring and Assessment Program (EMAP). The survey targeted estuaries along the outer coasts of Washington, Oregon and California, including the lower Columbi...

  12. MODIS water quality algorithms for northwest Florida estuaries

    EPA Science Inventory

    Synoptic and frequent monitoring of water quality parameters from satellite is useful for determining the health of aquatic ecosystems and development of effective management strategies. Northwest Florida estuaries are classified as optically-complex, or waters influenced by chlo...

  13. BACTERIOPLANKTON DYNAMICS IN A SUBTROPICAL ESTUARY: EVIDENCE FOR SUBSTRATE LIMITATION

    EPA Science Inventory

    Bacterioplankton abundance and metabolic characteristics were measured along a transect in Pensacola Bay, Florida, USA, to examine the factors that control microbial water column processes in this subtropical estuary. The microbial measures included 3 H-L-leucine incorporation, e...

  14. SPATIAL DISTRIBUTIONS OF BURROWING SHRIMP POPULATIONS IN TWO OREGON ESTUARIES

    EPA Science Inventory

    Thalassinid burrowing shrimp (Neotrypaea californiensis and Upogebia pugettensis) inhabit large expanses of Pacific estuarine tide flats, from British Columbia to Baja California. The spatial distribution of shrimp populations within estuaries has rarely been quantified because ...

  15. SAN JUAN BAY ESTUARY PROGRAM IMPLEMENTATION REVIEW ATTACHMENTS

    EPA Science Inventory

    A compilation of attachments referenced in the San Juan Bay Estuary Program Implementation Review (2004). Materials include, entity reports, water and sediment quality action plans, progress reports, correspondence with local municipalities and Puerto Rican governmental agencies,...

  16. Turbidity and sediment transport in a muddy sub-estuary

    NASA Astrophysics Data System (ADS)

    Uncles, R. J.; Stephens, J. A.

    2010-04-01

    Sub-estuaries, i.e. tidal creeks and also larger estuaries that branch off the stem of their main estuary, are commonplace in many estuarine systems. Their physical behaviour is affected not only by tributary inflows, winds and tides, but also by the properties and behaviour of their main estuary. Measurements extending over more than an annual cycle are presented for the Tavy Estuary, a sub-estuary of the Tamar Estuary, UK. Generally, waves are small in the Tavy because of the short wind fetch. A several-hour period of up-estuary winds, blowing at speeds of between 7 and 10 m s -1, generates waves with significant wave heights of 0.25 m and a wave periodicity of 1.7 s that are capable of eroding the bed over the shallow, ca. 1.5 m-deep mudflats. Waves also influence sedimentation within and near salt marsh areas. An estuarine turbidity maximum (ETM) occurs in the Tavy's main channel, close to the limit of salt intrusion at HW. Suspended particulate matter (SPM) concentrations typically are less than 40 mg l -1 at HW, although concentrations can exceed 80 mg l -1 when tides and winds are strong. Flood-tide SPM inputs to the Tavy from the Tamar are greater during high runoff events in the River Tamar and also at spring tides, when the Tamar has a high-concentration ETM. Higher SPM concentrations are experienced on the mudflats following initial inundation. Without wave resuspension, this is followed by a rapid decrease in SPM for most of the tide, indicating that the mudflats are depositional at those times. SPM concentrations on the mudflats again increase sharply prior to uncovering. Peak ebb tidal speeds at 0.15 m above the mudflat bed can exceed 0.26 m s -1 at spring tides and 0.4 m s -1 following high runoff events, which are sufficient to cause resuspension. Time-series measurements of sediment bed levels show strong seasonal variability. Higher and lower freshwater flows are associated with estimated, monthly-mean sediment transport that is directed out of, or into, the upper sub-estuary, respectively. Seasonal sediment transfers between the estuary and its sub-estuary are discussed.

  17. Continuous resistivity profiling data from the Corsica River Estuary, Maryland

    USGS Publications Warehouse

    Cross, V.A.; Bratton, J.F.; Worley, C.R.; Crusius, J.; Kroeger, K.D.

    2011-01-01

    Submarine groundwater discharge (SGD) into Maryland's Corsica River Estuary was investigated as part of a larger study to determine its importance in nutrient delivery to the Chesapeake Bay. The Corsica River Estuary represents a coastal lowland setting typical of much of the eastern bay. An interdisciplinary U.S. Geological Survey (USGS) science team conducted field operations in the lower estuary in April and May 2007. Resource managers are concerned about nutrients that are entering the estuary via SGD that may be contributing to eutrophication, harmful algal blooms, and fish kills. Techniques employed in the study included continuous resistivity profiling (CRP), piezometer sampling of submarine groundwater, and collection of a time series of radon tracer activity in surface water. A CRP system measures electrical resistivity of saturated subestuarine sediments to distinguish those bearing fresh water (high resistivity) from those with saline or brackish pore water (low resistivity). This report describes the collection and processing of CRP data and summarizes the results. Based on a grid of 67.6 kilometers of CRP data, low-salinity (high-resistivity) groundwater extended approximately 50-400 meters offshore from estuary shorelines at depths of 5 to >12 meters below the sediment surface, likely beneath a confining unit. A band of low-resistivity sediment detected along the axis of the estuary indicated the presence of a filled paleochannel containing brackish groundwater. The meandering paleochannel likely incised through the confining unit during periods of lower sea level, allowing the low-salinity groundwater plumes originating from land to mix with brackish subestuarine groundwater along the channel margins and to discharge. A better understanding of the spatial variability and geological controls of submarine groundwater flow beneath the Corsica River Estuary could lead to improved models and mitigation strategies for nutrient over-enrichment in the estuary and in other similar settings.

  18. Contamination and restoration of an estuary affected by phosphogypsum releases.

    PubMed

    Villa, M; Mosqueda, F; Hurtado, S; Mantero, J; Manjón, G; Periañez, R; Vaca, F; García-Tenorio, R

    2009-12-15

    The Huelva Estuary in Huelva, Spain, has been one of the most studied environmental compartments in the past years from the point of view of naturally occurring radioactive material (NORM) releases. It has been historically affected by waste releases, enriched in radionuclides from the U-decay series, from factories located in the area devoted to the production of phosphoric acid and phosphate fertilizers. Nevertheless, changes in national regulations forced a new waste management practice in 1998, prohibiting releases of phosphogypsum into the rivers. The input of natural radionuclides from phosphate factories to rivers was drastically reduced. Because of this there was a unique opportunity for the study of the response of a contaminated environmental compartment, specifically an estuary affected by tidal influences, after the cessation of the contaminant releases to, in this case, the Huelva Estuary (henceforth referred to as the Estuary). To investigate the environmental response to this new discharge regime, the specific activities of radionuclides 226Ra and 210Pb in water and sediment samples collected in four campaigns (from 1999 to 2005) were determined and compared with pre-1998 values. From this study it is possible to infer the most effective mechanisms of decontamination for the Estuary. Decontamination rates of 210Pb and 226Ra in the sediments and water have been calculated using exponential fittings and corresponding half-lives have been deduced from them. The cleaning half-life in the whole area of the Estuary is about 6 and 3.5 years for 226Ra and 210Pb respectively. The observed trend clearly shows that contamination of the Estuary by natural radionuclides is now decreasing and radioactive levels in waters and sediments are approaching the natural background references. This work attempts to evaluate whether it can be expected that the decontamination of the enhanced levels of natural radioactivity in the Estuary can be performed via natural processes. PMID:19822348

  19. Stable carbon and nitrogen isotope biogeochemistry in the Delaware estuary

    Microsoft Academic Search

    L. A. Cifuentesl; J. H. SHARP; MARILYN L. FOGEL

    1988-01-01

    ,Qbstract Seasonal variability in stable carbon (S'XZ) and nitrogen (b15N) isotope ratios was observed in suspended particulate matter of the Delaware estuary. Two major pools of organic matter were found in the estuary-phytoplankton growing in situ and a mixture of planktonic and terrestrial detritus. In general, the 6°C and 615N of suspended particulate matter reflected planktonic dom- inance. With the

  20. Intertidal morphology change following Spartina anglica introduction, Tamar Estuary, Tasmania

    NASA Astrophysics Data System (ADS)

    Sheehan, Matthew R.; Ellison, Joanna C.

    2014-08-01

    The surface morphology and sediment characteristics of introduced Spartina anglica marshes of the Tamar Estuary were analysed using a combination of spatial mapping, land-based topographical surveys, sediment coring and identification of the pre-introduction surface. Such a morphological investigation of estuarine change following Spartina introduction has not been attempted elsewhere before. A difference was found between marshes in upper and lower estuary. Surface topography of Type-1 marshes of the upper estuary was found to be independent of the pre-Spartina surface morphology, with deeper vertical development and exhibiting a flat to slightly concave upper marsh, a convex ridge in the outer mid marsh, and a relatively steeply graded convex lower marsh. Type-2 marshes of the lower estuary were thinner in vertical development, and with surface topography dictated by the underlying pre-Spartina surface. The difference was found to be due to variations in environmental conditions in sediment supply and wave/current exposure between the two regions rather being an indication of relative maturity. The seaward edge of marshes was found to be 0.5 m lower at the seaward end of the Tamar relative to the landward, reflecting tidal amplification up this confined estuary. While Spartina marshes are accretionary, surveys demonstrated retreat of the seaward margins throughout the estuary over the past 17 years, and the development of erosional scarps in Type-1 marshes. Spatial mapping identified 374 ha of S. anglica infestation within the Tamar Estuary, with Type-1 marshes occupying 240 ha and Type-2 marshes occupying 134 ha. Topographic profiles and stratigraphic data were used to estimate total sediment volumes trapped by Spartina in the Tamar Estuary, finding approximately 1,193,441 m3 of material to have been trapped beneath Spartina since its introduction in 1947, of which between 14 and 28% has been Spartina-derived organic matter.

  1. Juvenile salmon usage of the skeena river estuary.

    PubMed

    Carr-Harris, Charmaine; Gottesfeld, Allen S; Moore, Jonathan W

    2015-01-01

    Migratory salmon transit estuary habitats on their way out to the ocean but this phase of their life cycle is more poorly understood than other phases. The estuaries of large river systems in particular may support many populations and several species of salmon that originate from throughout the upstream river. The Skeena River of British Columbia, Canada, is a large river system with high salmon population- and species-level diversity. The estuary of the Skeena River is under pressure from industrial development, with two gas liquefaction terminals and a potash loading facility in various stages of environmental review processes, providing motivation for understanding the usage of the estuary by juvenile salmon. We conducted a juvenile salmonid sampling program throughout the Skeena River estuary in 2007 and 2013 to investigate the spatial and temporal distribution of different species and populations of salmon. We captured six species of juvenile anadromous salmonids throughout the estuary in both years, and found that areas proposed for development support some of the highest abundances of some species of salmon. Specifically, the highest abundances of sockeye (both years), Chinook in 2007, and coho salmon in 2013 were captured in areas proposed for development. For example, juvenile sockeye salmon were 2-8 times more abundant in the proposed development areas. Genetic stock assignment demonstrated that the Chinook salmon and most of the sockeye salmon that were captured originated from throughout the Skeena watershed, while some sockeye salmon came from the Nass, Stikine, Southeast Alaska, and coastal systems on the northern and central coasts of British Columbia. These fish support extensive commercial, recreational, and First Nations fisheries throughout the Skeena River and beyond. Our results demonstrate that estuary habitats integrate species and population diversity of salmon, and that if proposed development negatively affects the salmon populations that use the estuary, then numerous fisheries would also be negatively affected. PMID:25749488

  2. Attenuation of rare earth elements in a boreal estuary

    NASA Astrophysics Data System (ADS)

    Åström, Mats E.; Österholm, Peter; Gustafsson, Jon Petter; Nystrand, Miriam; Peltola, Pasi; Nordmyr, Linda; Boman, Anton

    2012-11-01

    This study focuses on attenuation of rare earth elements (REE) when a boreal creek, acidified and loaded with REE and other metals as a result of wetland drainage, empties into a brackish-water estuary (salinity < 6‰). Surface water was collected in a transect from the creek mouth to the outer estuary, and settling (particulate) material in sediment traps moored at selected locations in the estuary. Ultrafiltration, high-resolution ICP-MS and modeling were applied on the waters, and a variety of chemical reagents were used to extract metals from the settling material. Aluminium, Fe and REE transported by the acidic creek were extensively removed in the inner/central estuary where the acidic water was neutralised, whereas Mn was relatively persistent in solution and thus redistributed to particles and deposited further down the estuary. The REE removal was caused by several contemporary mechanisms: co-precipitation with oxyhydroxides (mainly Al but also Fe), complexation with flocculating humic substances and sorption to suspended particles. Down estuary the dissolved REE pool, remaining after removal, was fractionated: the <1 kDa pool became depleted in the middle REE and the colloidal (0.45 ?m-1 kDa) pool depleted in the middle and heavy REE. This fractionation was controlled by the removal process, such that those REE with highest affinity for the settling particles became most depleted in the remaining dissolved pool. Modeling, based on Visual MINTEQ version 3.0 and the Stockholm Humic Model after revision and updating, predicted that the dissolved (<0.45 ?m) REE pool in the estuary is bound almost entirely to humic substances. Acid sulphate soils, the source of the REE and other metals in the creek water, are widespread on coastal plains worldwide and therefore the REE attenuation patterns and mechanisms identified in the studied estuary are relevant for recognition of similar geochemical processes and conditions in a variety of coastal locations.

  3. Juvenile Salmon Usage of the Skeena River Estuary

    PubMed Central

    Carr-Harris, Charmaine; Gottesfeld, Allen S.; Moore, Jonathan W.

    2015-01-01

    Migratory salmon transit estuary habitats on their way out to the ocean but this phase of their life cycle is more poorly understood than other phases. The estuaries of large river systems in particular may support many populations and several species of salmon that originate from throughout the upstream river. The Skeena River of British Columbia, Canada, is a large river system with high salmon population- and species-level diversity. The estuary of the Skeena River is under pressure from industrial development, with two gas liquefaction terminals and a potash loading facility in various stages of environmental review processes, providing motivation for understanding the usage of the estuary by juvenile salmon. We conducted a juvenile salmonid sampling program throughout the Skeena River estuary in 2007 and 2013 to investigate the spatial and temporal distribution of different species and populations of salmon. We captured six species of juvenile anadromous salmonids throughout the estuary in both years, and found that areas proposed for development support some of the highest abundances of some species of salmon. Specifically, the highest abundances of sockeye (both years), Chinook in 2007, and coho salmon in 2013 were captured in areas proposed for development. For example, juvenile sockeye salmon were 2–8 times more abundant in the proposed development areas. Genetic stock assignment demonstrated that the Chinook salmon and most of the sockeye salmon that were captured originated from throughout the Skeena watershed, while some sockeye salmon came from the Nass, Stikine, Southeast Alaska, and coastal systems on the northern and central coasts of British Columbia. These fish support extensive commercial, recreational, and First Nations fisheries throughout the Skeena River and beyond. Our results demonstrate that estuary habitats integrate species and population diversity of salmon, and that if proposed development negatively affects the salmon populations that use the estuary, then numerous fisheries would also be negatively affected. PMID:25749488

  4. Typical features of particulate phosphorus in the Seine estuary (France)

    Microsoft Academic Search

    Julien Némery; Josette Garnier

    2007-01-01

    During the 2001–2002 hydrological cycle, 8,000 tons P year?1 (44% as particulate phosphorus) originating from the Seine basin entered the Seine estuary. P content in suspended sediments\\u000a (SS) is 2.9 g P kg?1 (80% as inorganic form) at Poses (the upstream limit of the Seine estuary). During the transfer from Poses to Caudebec (the\\u000a limit of saline water intrusion), Particulate

  5. Biological effects of anthropogenic contaminants in the San Francisco Estuary

    USGS Publications Warehouse

    Thompson, B.; Adelsbach, T.; Brown, C.; Hunt, J.; Kuwabara, J.; Neale, J.; Ohlendorf, H.; Schwarzbach, S.; Spies, R.; Taberski, K.

    2007-01-01

    Concentrations of many anthropogenic contaminants in the San Francisco Estuary exist at levels that have been associated with biological effects elsewhere, so there is a potential for them to cause biological effects in the Estuary. The purpose of this paper is to summarize information about biological effects on the Estuary's plankton, benthos, fish, birds, and mammals, gathered since the early 1990s, focusing on key accomplishments. These studies have been conducted at all levels of biological organization (sub-cellular through communities), but have included only a small fraction of the organisms and contaminants of concern in the region. The studies summarized provide a body of evidence that some contaminants are causing biological impacts in some biological resources in the Estuary. However, no general patterns of effects were apparent in space and time, and no single contaminant was consistently related to effects among the biota considered. These conclusions reflect the difficulty in demonstrating biological effects due specifically to contamination because there is a wide range of sensitivity to contaminants among the Estuary's many organisms. Additionally, the spatial and temporal distribution of contamination in the Estuary is highly variable, and levels of contamination covary with other environmental factors, such as freshwater inflow or sediment-type. Federal and State regulatory agencies desire to develop biological criteria to protect the Estuary's biological resources. Future studies of biological effects in San Francisco Estuary should focus on the development of meaningful indicators of biological effects, and on key organism and contaminants of concern in long-term, multifaceted studies that include laboratory and field experiments to determine cause and effect to adequately inform management and regulatory decisions. ?? 2006 Elsevier Inc. All rights reserved.

  6. Nitrogen and phosphorus budgets of the Changjiang River estuary

    Microsoft Academic Search

    Xiang’an Li; Zhiming Yu; Xiuxian Song; Xihua Cao; Yongquan Yuan

    2011-01-01

    Eutrophication has emerged as a key environmental problem in Chinese coastal waters, especially in the Changjiang (Yangtze)\\u000a River estuary. In this area, large nutrient inputs result in frequent harmful algal blooms and serious hypoxia in bottom waters.\\u000a Four cruises were made in the estuary in 2006 to assess the concentration and distribution of dissolved inorganic nitrogen\\u000a (DIN) and phosphorus (DIP).

  7. Columbia Bay, Alaska: an 'upside down' estuary

    USGS Publications Warehouse

    Walters, R.A.; Josberger, E.G.; Driedger, C.L.

    1988-01-01

    Circulation and water properties within Columbia Bay, Alaska, are dominated by the effects of Columbia Glacier at the head of the Bay. The basin between the glacier terminus and the terminal moraine (sill depth of about 22 m) responds as an 'upside down' estuary with the subglacial discharge of freshwater entering at the bottom of the basin. The intense vertical mixing caused by the bouyant plume of freshwater creates a homogeneous water mass that exchanges with the far-field water through either a two- or a three-layer flow. In general, the glacier acts as a large heat sink and creates a water mass which is cooler than that in fjords without tidewater glaciers. The predicted retreat of Columbia Glacier would create a 40 km long fjord that has characteristics in common with other fjords in Prince William Sound. ?? 1988.

  8. Monitoring Rehabilitation in Temperate North American Estuaries

    SciTech Connect

    Rice, Casimir A.; Hood, W Gregory; Tear, Lucinda M.; Simenstad, Charles; Williams, Gregory D.; Johnson, L. L.; Feist, B. E.; Roni, P.

    2005-02-01

    In this chapter, we propose that monitoring rehabilitation in estuarine ecosystems by necessity requires quantifying relationships between dynamic estuarine processes and sensitive indicators of ecosystem function. While we do discuss temperate systems in general, emphasis is placed on anadromous salmon habitats in the Pacific Northwest because anadromous fishes are such a major focus of rehabilitation efforts, and present some of the greater challenges in linking function of one segment of their life history to conditions in a specific habitat. We begin with a basic overview of the ecological and socioeconomic significance of, as well as anthropogenic effects on, estuaries. Next, we briefly summarize the various kinds of estuarine rehabilitation historically practiced in temperate regions, and review estuarine rehabilitation monitoring design and methods, highlighting the unique challenges involved in monitoring estuarine systems. We then close with a summary and conclusions.

  9. Winds and the orientation of a coastal plane estuary plume

    NASA Astrophysics Data System (ADS)

    Xia, Meng; Xie, Lian; Pietrafesa, Leonard J.

    2010-10-01

    Based on a calibrated coastal plane estuary plume model, ideal model hindcasts of estuary plumes are used to describe the evolution of the plume pattern in response to river discharge and local wind forcing by selecting a typical partially mixed estuary (the Cape Fear River Estuary or CFRE). With the help of an existing calibrated plume model, as described by Xia et al. (2007), simulations were conducted using different parameters to evaluate the plume behavior type and its change associated with the variation of wind forcing and river discharge. The simulations indicate that relatively moderate winds can mechanically reverse the flow direction of the plume. Downwelling favorably wind will pin the plume to the coasts while the upwelling plume could induce plume from the left side to right side in the application to CFRE. It was found that six major types of plumes may occur in the estuary and in the corresponding coastal ocean. To better understand these plumes in the CFRE and other similar river estuary systems, we also investigated how the plumes transition from one type to another. Results showed that wind direction, wind speed, and sometimes river discharge contribute to plume transitions.

  10. Ecological Engineering Practices for the Reduction of Excess Nitrogen in Human-Influenced Landscapes: A Guide for Watershed Managers

    EPA Science Inventory

    Excess nitrogen (N) in freshwater systems, estuaries, and coastal areas has well-documented deleterious effects on ecosystems. Ecological engineering practices (EEPs) may be effective at decreasing nonpoint source N leaching to surface and groundwater. However, few studies have s...

  11. The Feasibility of Cask \\

    Microsoft Academic Search

    K P Ziock; P Vanier; L Forman; G Caffrey; J Wharton; A Lebrun

    2005-01-01

    This report documents a week-long measurement campaign conducted on six, dry-storage, spent-nuclear-fuel storage casks at the Idaho National Laboratory. A gamma-ray imager, a thermal-neutron imager and a germanium spectrometer were used to collect data on the casks. The campaign was conducted to examine the feasibility of using the cask radiation signatures as unique identifiers for individual casks as part of

  12. 77 FR 34029 - Notice of Availability of the Draft Feasibility Study/Environmental Impact Statement for the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-08

    ...DEFENSE Department of the Army; Corps of Engineers Notice of Availability of the Draft Feasibility...Department of the Army, U.S. Army Corps of Engineers, DoD. ACTION: Notice of availability...as amended, the U.S. Army Corps of Engineers has prepared a Draft Feasibility...

  13. Engineering Engineering

    E-print Network

    Zhang, Junshan

    Phillip McClay Principal Analog Engineer Primarion Wally Meinell Group Manager Texas Instruments Robert Awards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 - 11 Feature Story AND SIDEBAR STORIES Faculty Bios

  14. Methane and nitrous oxide emissions from a subtropical estuary (the Brisbane River estuary, Australia).

    PubMed

    Musenze, Ronald S; Werner, Ursula; Grinham, Alistair; Udy, James; Yuan, Zhiguo

    2014-02-15

    Methane (CH4) and nitrous oxide (N2O) are two key greenhouse gases. Their global atmospheric budgeting is, however, flout with challenges partly due to lack of adequate field studies determining the source strengths. Knowledge and data limitations exist for subtropical and tropical regions especially in the southern latitudes. Surface water methane and nitrous oxide concentrations were measured in a subtropical estuarine system in the southern latitudes in an extensive field study from 2010 to 2012 and water-air fluxes estimated using models considering the effects of both wind and flow induced turbulence. The estuary was found to be a strong net source of both CH4 and N2O all-year-round. Dissolved N2O concentrations ranged between 9.1 ± 0.4 to 45.3 ± 1.3 nM or 135 to 435% of atmospheric saturation level, while CH4 concentrations varied between 31.1 ± 3.7 to 578.4 ± 58.8 nM or 1210 to 26,430% of atmospheric saturation level. These results compare well with measurements from tropical estuarine systems. There was strong spatial variability with both CH4 and N2O concentrations increasing upstream the estuary. Strong temporal variability was also observed but there were no clear seasonal patterns. The degree of N2O saturation significantly increased with NOx concentrations (r(2)=0.55). The estimated water-air fluxes varied between 0.1 and 3.4 mg N2O m(-2)d(-1) and 0.3 to 27.9 mg CH4 m(-2)d(-1). Total emissions (CO2-e) were N2O (64%) dominated, highlighting the need for reduced nitrogen inputs into the estuary. Choice of the model(s) for estimation of the gas transfer velocity had a big bearing on the estimated total emissions. PMID:24333994

  15. The status of fish conservation in South African estuaries.

    PubMed

    Whitfield, A K; Cowley, P D

    2010-06-01

    Estuary-dependent fish species are defined as those taxa whose populations would be adversely affected by the loss of estuarine habitats. Of the 155 species regularly recorded in South African estuaries, only 32 (21%) are completely dependent on these systems, but this figure increases to 103 species (66%) if partially dependent taxa are included in the analysis. The conservation of fishes in estuaries on the subcontinent is threatened by a number of factors, including habitat degradation, disruption of essential ecological processes, hydrological manipulations, environmental pollution, overexploitation due to fishing activities and, more recently, climate change and the effects of introduced aquatic animals. Although major threats to fishes are usually linked to environmental degradation, there is increasing evidence that the stocks of certain fish species are overexploited or collapsed. Fish conservation and fisheries management does not depend on the implementation of a single action, but rather the co-ordination of a detailed plan, often in a multidisciplinary context. Some examples of innovative means of contributing to estuarine fish conservation in a South African context include the determination and implementation of the ecological freshwater requirements for estuaries, the zoning of estuaries for different uses and the recognition that the maintenance of ecological processes are vital to aquatic ecosystem health. Apart from the designation of protected areas, the main direct means of conserving fish species and stocks include habitat conservation, controls over fishing methods, effort, efficiency and seasonality, pollution control and the prevention of artificial manipulation of estuary mouths. Since becoming a democracy in 1994, environmental legislation, policy and institutional arrangements in South Africa have undergone some major changes, which, if fully implemented, will be very positive for fish conservation in estuaries on the subcontinent. PMID:20557655

  16. A DATA SYSTEM FOR INTEGRATING DATA FROM LANDSCAPES, STREAMS AND ESTUARIES

    EPA Science Inventory

    Estuaries are natural integrators of substances and processes that occur internally and externally (watersheds, ocean, atmosphere). Watershed activities that contribute fresh water, nutrients, contaminants, and suspended solids have a strong effect on the health of estuaries. Res...

  17. San Francisco Estuary Regional Monitoring Program for Trace Substances Conceptual Framework and Rationale

    E-print Network

    San Francisco Estuary Regional Monitoring Program for Trace Substances Conceptual Framework Estuary Regional Monitoring Program for Trace Substances Conceptual Framework and Rationale development of a new component for the Status and Trends Program to monitor biological exposure and effects

  18. CLASSIFYING OREGON ESTUARIES BY HABITAT: ANALYSIS OF EXISTING DATA AND A PROPOSAL FOR A PILOT STUDY

    EPA Science Inventory

    Because many estuarine resources are linked to benthic habitats, classification of estuaries by habitat types may prove a relevant approach for grouping estuaries with similar ecological values and vulnerability to landscape alterations. As a first step, we evaluated whether pub...

  19. 77 FR 15722 - Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-16

    ...using heavy equipment for the duration...the lagoon management period. Monitoring...to estuary management activities...training includes equipment operators...to estuary management activities...use of heavy equipment and...

  20. 78 FR 14985 - Takes of Marine Mammals Incidental to Specified Activities; Russian River Estuary Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-08

    ...using heavy equipment for the duration...the lagoon management period. Monitoring...to estuary management activities...training includes equipment operators...to estuary management activities...use of heavy equipment and...

  1. Columbia River Estuary Ecosystem Classification Hydrogeomorphic Reach

    USGS Publications Warehouse

    Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

  2. Columbia River Estuary Ecosystem Classification Geomorphic Catena

    USGS Publications Warehouse

    Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

  3. Columbia River Estuary Ecosystem Classification Ecosystem Complex

    USGS Publications Warehouse

    Cannon, Charles M.; Ramirez, Mary F.; Heatwole, Danelle W.; Burke, Jennifer L.; Simenstad, Charles A.; O'Connor, Jim E.; Marcoe, Keith Marcoe

    2012-01-01

    Estuarine ecosystems are controlled by a variety of processes that operate at multiple spatial and temporal scales. Understanding the hierarchical nature of these processes will aid in prioritization of restoration efforts. This hierarchical Columbia River Estuary Ecosystem Classification (henceforth "Classification") of the Columbia River estuary is a spatial database of the tidally-influenced reaches of the lower Columbia River, the tidally affected parts of its tributaries, and the landforms that make up their floodplains for the 230 kilometers between the Pacific Ocean and Bonneville Dam. This work is a collaborative effort between University of Washington School of Aquatic and Fishery Sciences (henceforth "UW"), U.S. Geological Survey (henceforth "USGS"), and the Lower Columbia Estuary Partnership (henceforth "EP"). Consideration of geomorphologic processes will improve the understanding of controlling physical factors that drive ecosystem evolution along the tidal Columbia River. The Classification is organized around six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. For Levels 4 and 5, we mapped landforms within the Holocene floodplain primarily by visual interpretation of Light Detection and Ranging (LiDAR) topography supplemented with aerial photographs, Natural Resources Conservation Service (NRCS) soils data, and historical maps. Mapped landforms are classified as to their current geomorphic function, the inferred process regime that formed them, and anthropogenic modification. Channels were classified primarily by a set of depth-based rules and geometric relationships. Classification Level 5 floodplain landforms ("geomorphic catenae") were further classified based on multivariate analysis of land-cover within the mapped landform area and attributed as "sub-catena". The extent of detailed mapping is the interpreted Holocene geologic floodplain of the tidal Columbia River and its tributaries to the estimated head of tide. The extent of this dataset also includes tributary valleys that are not mapped in detail. The upstream extents of tributary valleys are an estimation of the limit of Columbia River influence and are for use as containers in future analyses. The geologic floodplain is the geomorphic surface that is actively accumulating sediment through occasional overbank deposition. Most features within the geologic floodplain are considered to be formed during the recent (Holocene-epoch) climatic regime. There are bedrock and pre-Holocene sedimentary deposits included where they are surrounded by Holocene sediment accumulations or have been shaped by Holocene floods. In some places, Holocene landforms such as landslides, tributary fans, and coastal dunes are mapped that extend outside of the modern floodplain. This map is not a floodplain hazard map or delineation of actual flood boundaries. Although wetlands are included in the Classification, they are based on different criteria than jurisdictional wetlands. The extent of mapping may differ from the actual limit of tidal influence.

  4. Hydrodynamic controls on oxygen dynamics in a riverine salt wedge estuary, the Yarra River estuary, Australia

    NASA Astrophysics Data System (ADS)

    Bruce, L. C.; Cook, P. L. M.; Teakle, I.; Hipsey, M. R.

    2014-04-01

    Oxygen depletion in coastal and estuarine waters has been increasing rapidly around the globe over the past several decades, leading to decline in water quality and ecological health. In this study we apply a numerical model to understand how salt wedge dynamics, changes in river flow and temperature together control oxygen depletion in a micro-tidal riverine estuary, the Yarra River estuary, Australia. Coupled physical-biogeochemical models have been previously applied to study how hydrodynamics impact upon seasonal hypoxia; however, their application to relatively shallow, narrow riverine estuaries with highly transient patterns of river inputs and sporadic periods of oxygen depletion has remained challenging, largely due to difficulty in accurately simulating salt wedge dynamics in morphologically complex areas. In this study we overcome this issue through application of a flexible mesh 3-D hydrodynamic-biogeochemical model in order to predict the extent of salt wedge intrusion and consequent patterns of oxygen depletion. The extent of the salt wedge responded quickly to the sporadic riverine flows, with the strength of stratification and vertical density gradients heavily influenced by morphological features corresponding to shallow points in regions of tight curvature ("horseshoe" bends). The spatiotemporal patterns of stratification led to the emergence of two "hot spots" of anoxia, the first downstream of a shallow region of tight curvature and the second downstream of a sill. Whilst these areas corresponded to regions of intense stratification, it was found that antecedent conditions related to the placement of the salt wedge played a major role in the recovery of anoxic regions following episodic high flow events. Furthermore, whilst a threshold salt wedge intrusion was a requirement for oxygen depletion, analysis of the results allowed us to quantify the effect of temperature in determining the overall severity and extent of hypoxia and anoxia. Climate warming scenarios highlighted that oxygen depletion is likely to be exacerbated through changes in flow regimes and warming temperatures; however, the increasing risk of hypoxia and anoxia can be mitigated through management of minimum flow allocations and targeted reductions in organic matter loading. A simple statistical model (R2 > 0.65) is suggested to relate riverine flow and temperature to the extent of estuary-wide anoxia.

  5. United States Air Force 611th Air Support Group/Civil Engineering Squadron, Elmendorf AFB, Alaska. Remedial investigation and feasibility study: Oliktok Point Radar Installation, Alaska. Volume 1. (Includes appendices a - b)

    SciTech Connect

    NONE

    1996-04-15

    This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Oliktok Point radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.

  6. From the utilization point of view, the two approaches seem to United States Air Force 611th Air Support Group/Civil Engineering Squadron, Elmendorf AFB, Alaska. Remedial investigation and feasibility study Point Barrow Radar Installation, Alaska. Final report

    SciTech Connect

    Karmi, S.

    1996-02-19

    This report presents the findings of Remedial Investigations and Feasibility Studies at sites located at the Point Barrow radar installation in northern Alaska. The sites were characterized based on sampling and analyses conducted during Remedial Investigation activities performed during August and September 1993.

  7. Lasers for engine ignition

    NASA Astrophysics Data System (ADS)

    Graham-Rowe, Duncan; Won, Rachel

    2008-09-01

    The pollutant emissions and high-energy consumption of combustion engines using conventional spark plugs have long been serious environmental problems. Now, it has been demonstrated that lasers can provide a feasible green alternative. Duncan Graham-Rowe reports.

  8. Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2009

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Bryson, Amanda J.; Cameron, April; Coleman, Andre M.; Corbett, C.; Dawley, Earl M.; Ebberts, Blaine D.; Kauffman, Ronald; Roegner, G. Curtis; Russell, Micah T.; Silva, April; Skalski, John R.; Thom, Ronald M.; Vavrinec, John; Woodruff, Dana L.; Zimmerman, Shon A.

    2010-10-26

    This is the sixth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the lower Columbia River and estuary (LCRE). The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers Portland District (USACE) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), the Columbia River Estuary Study Taskforce (CREST), and the University of Washington. The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the 235-km-long LCRE. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2009, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tidegate replacement vs. culvert replacement vs. dike breach).

  9. Modelling of cohesive sediment dynamics in tidal estuarine systems: Case study of Tagus estuary, Portugal

    NASA Astrophysics Data System (ADS)

    Franz, G.; Pinto, L.; Ascione, I.; Mateus, M.; Fernandes, R.; Leitão, P.; Neves, R.

    2014-12-01

    Cohesive sediment dynamics in estuarine systems is a major issue in water quality and engineering problems. Numerical models can help to assess the complex dynamics of cohesive sediments, integrating the information collected in monitoring studies. Following a numerical approach we investigated the main factors that influence the cohesive sediment dynamics in an estuarine system composed of large mudflats (Tagus estuary, Portugal). After a spin up period of the bottom layer and considering the combined effect of waves and currents on the bottom shear stress, the dynamics of cohesive sediment during the fortnightly and daily erosion-sedimentation cycle was properly reproduced by the model. The results of cohesive suspended sediments were validated with data from sixteen monitoring stations located along the estuary and turbidity data measured by two multiparametric probes. The hydrodynamics were previously validated by harmonic analysis and with ADCP data. Although tidal currents are the major cause of cohesive sediment erosion, the results suggest that wind waves also play an important role. The simulated sediment mass involved in the fortnightly tidal cycle was in the same order of magnitude of the annual load from the rivers, as observed in previous studies based on field data.

  10. Observations of Floc Sizes in a Muddy Estuary

    NASA Astrophysics Data System (ADS)

    Uncles, R. J.; Bale, A. J.; Stephens, J. A.; Frickers, P. E.; Harris, C.

    2010-04-01

    Measurements are presented of median floc diameters and associated environmental data over spring-tide tidal cycles at two stations in the muddy Tamar Estuary, UK, for winter, spring and summer conditions. The particulate organic carbon and particulate total carbon contents of mudflats and SPM (suspended particulate matter) at the stations, together with other evidence, indicates that much of the SPM was derived from mud sources that were located between the two stations during winter and spring, and from very mobile sediment sources in the upper estuary during summer. Observed in-situ median floc sizes varied widely, from <50 to >500 ?m and rapid settling of particles close to HW and LW (high and low water) left only the smaller flocs in suspension. Time-series of depth-averaged median floc sizes generally were most closely, positively, correlated with depth-averaged SPM concentrations. Floc diameters tended to reach maximum median sizes near the time when SPM concentrations were highest. These high concentrations were in turn largely generated by resuspension of sediment during the fastest current speeds. Although such correlations may have arisen because of SPM-driven floc growth - despite fast tidal currents - there is also the possibility that tough aggregates were eroded from the intertidal mudflats and mudbanks. Although a hypothesis, such large aggregates of fine sediment may have resulted from the binding together of very fine bed particles by sticky extracellular polymeric substances (EPS) coatings, produced by benthic diatoms and by other biologically-mediated activity. A rapid reduction of SPM occurred at the up-estuary station within 2.5 h of HW on the flood, when decelerating currents were still relatively fast. It appears that at least two processes were at work: localised settling of the largest flocs and up-estuary transport in which large flocs were transported further into the estuary before settling into the Tamar's ETM (estuarine turbidity maximum) over the HW-slack period. Up-estuary advection of large flocs and their eventual settling would place the down-estuary edge of the ETM above the upper-estuary station during summer, spring-tide conditions. This position of the ETM was observed close to HW during longitudinal surveys of the estuary.

  11. Dynamics of intertidal flats in the Loire estuary

    NASA Astrophysics Data System (ADS)

    Kervella, Stephane; Sottolichio, Aldo; Bertier, Christine

    2014-05-01

    Tidal flats form at the edges of many tidal estuaries, and are found in broad climatic regions. Their evolution plays a fundamental role in maintaining the morphodynamic equilibrium of an estuary. The Loire estuary is one of the largest macrotidal systems of the french atlantic coast. Since 200 years, its geometry has been drastically modified through channeling, deepening, embanking, infilling of secondary channels, etc. These works altered many intertidal areas. In the recent years, efforts for the rectification of the morphology have been made in order to restore the ecology of the estuary. In this context, it is crucial to better understand the dynamics of intertidal flats, still poorly understood in this estuary. The aim of this work is to analyse a series of original observations conducted for the first time in two intertidal flats of the central Lore estuary between 2008 and 2010. The tidal flats are situated in the northern bank, at 12 and 17 km upstream from the mouth respectively. Six Altus altimeters were deployed at two cross shore transects, measuring continuously and at a high-frequency bed altimetry and water level, providing information on tide and waves. At the semi-diurnal tidal scale, the surficial sediment of intertidal flats is permanently mobilized. Altimetry variations are low, and their amplitude varies as a function of tides and river flow. At the scale of several months, the sedimentation is controlled by the position of the turbidity maximum (and therefore by the river flow) and also by the tidal amplitude. During low river flow periods, altimetry variations are only due to tidal cycles. During decaying tides, suspended sediment settle mainly on the lower part of the tidal flats, forming fluid mud layers of several cm thick, which can consolidate rapidly; under rising tides, the increasing of tidal currents promotes erosion. During periods of high river flow, the turbidity maximum shifts to the lower estuary. The higher suspended sediment concentration increases deposition and erosion rates, especially in the lower parts of the flats, where continuous sedimentary accretion is favoured by the proximity of the channel. During this period, reinforcement of current veolocities limits deposition in the central and high portion of the flats, where erosion is enhanced. The first rivers floods remove fluid mud in the upper estuary, previously deposited during the dry season, which is transported seawards. The transported suspended sediment settles massively in the lower parts of the flats and in the channels. The deposited mud is eroded a few days later. These results provide useful information to better understand the dynamics of the Loire estuary, as well as they give in situ data to be compared with numerical modelling.

  12. PEER REVIEW OF PECONIC ESTUARY PROGRAM HYDRODYNAMIC AND WATER QUALITY (EUTROPHICATION) MODEL

    EPA Science Inventory

    The Peconic Estuary is located on the eastern end of Long Island, New York. Under the Federal Clean Water Act, the Peconic Estuary was named an "Estuary of National Significance" in 1992. Because of its high concentration of rare, threatened and endangered species and habitats,...

  13. The Ichthyoplankton of Selected Estuaries in Sarawak and Sabah: Composition, Distribution and Habitat Affinities

    Microsoft Academic Search

    S. J. M. Blaber; M. J. Farmer; D. A. Milton; J. Pang; O. Boon-Teck; P. Wong

    1997-01-01

    The ichthyoplankton assemblages of 23 estuaries in Sarawak and Sabah were surveyed with particular reference to the culturally and commercially important clupeidTenualosa toli. The species composition, distribution and density of all fish larvae were recorded, together with the physical characteristics of each estuary. A more detailed study was made of the Lupar and Lassa estuaries, which are the ‘core area’

  14. Species composition, community structure and zoogeography of fishes of mangrove estuaries in the Solomon Islands

    Microsoft Academic Search

    S. J. M. Blaber; D. A. Milton

    1990-01-01

    Mangrove estuaries in the Solomon Islands are well developed, but are small and isolated from each other by extensive fringing coral reef lagoons. A total of 136 species of fish were recorded from 13 estuaries (6 estuaries in Kolombangara, 3 in New Georgia, 3 in Rendova and 1 in the Florida Group); none contained more than 50 species. Sampling took

  15. Two decades of fish habitat restoration and bioengineering on the Fraser River estuary, British Columbia, Canada

    Microsoft Academic Search

    C. D. Levings

    2004-01-01

    The Fraser River estuary is the most important estuary on Canada's Pacific coast. To achieve a net gain of fish habitat, a goal of Canada's fisheries management policy, a large number of habitat restoration projects have been conducted in the estuary since 1980. In this paper the author focuses on bioengineering aspects of some of the older projects and an

  16. A Simple Model of Nitrogen Concentration, Throughput, and Denitrification in Estuaries

    EPA Science Inventory

    The Estuary Nitrogen Model (ENM) is a mass balance model that includes calculation of nitrogen losses within bays and estuaries using system flushing time. The model has been used to demonstrate the dependence of throughput and denitrification of nitrogen in bays and estuaries on...

  17. Structure, variability, and salt flux in a strongly forced salt wedge estuary

    Microsoft Academic Search

    David K. Ralston; W. Rockwell Geyer; James A. Lerczak

    2010-01-01

    The tidally varying circulation, stratification, and salt flux mechanisms are investigated in a shallow salt wedge estuary where fluvial and tidal velocities are large and the steady baroclinic circulation is comparatively weak. The study integrates field observations and numerical simulations of the Merrimack River estuary. At moderate to high discharge the estuary is short and highly stratified, while at lower

  18. San Francisco Estuary Regional Monitoring Program for Trace Substances Report of the 2003 Program Review

    E-print Network

    San Francisco Estuary Regional Monitoring Program for Trace Substances Report of the 2003 Program Review REGIONAL MONITORING PROGRAM FOR TRACE SUBSTANCES in the SAN FRANCISCO ESTUARY Mr. Robert Berger Dr Review REGIONAL MONITORING PROGRAM FOR TRACE SUBSTANCES in the SAN FRANCISCO ESTUARY Panel: Mr. Robert

  19. Sediment Respiration and Nitrogen Cycling along a Eutrophic Gradient in a Shallow, Coastal Estuary

    E-print Network

    Vallino, Joseph J.

    Sediment Respiration and Nitrogen Cycling along a Eutrophic Gradient in a Shallow, Coastal Estuary Respiration and Nitrogen Cycling along a Eutrophic Gradient in a Shallow, Coastal Estuary Semester on nitrogen cycling in West Falmouth Harbor, a shallow, coastal estuary on Cape Cod. Our project also

  20. Increased Susceptibility of Juvenile Chinook Salmon from a Contaminated Estuary to Vibrio anguillarum

    Microsoft Academic Search

    Mary R. Arkoosh; Ed Casillas; Paul Huffman; Ethan Clemons; Joy Evered; John E. Stein; Usha Varanasi

    1998-01-01

    Previous studies have shown that juvenile chinook salmon Oncorhynchus tshawytscha from a contaminated estuary of Puget Sound, Washington, are immunosuppressed. Immunosuppressed fish may be more susceptible to disease and ultimately experience an increase in mortality. To evaluate this possibility, differences in susceptibility to a marine pathogen in outmigrating juvenile chinook salmon from an urban estuary and a nonurban estuary in

  1. Antibiotic Resistance of Escherichia coli Serotypes from Cochin Estuary

    PubMed Central

    Sukumaran, Divya P.; Durairaj, Srinivasan; Abdulla, Mohamed Hatha

    2012-01-01

    This study aimed at detecting the prevalence of antibiotic-resistant serotypes of Escherichia coli in Cochin estuary, India. E. coli strains were isolated during the period January 2010–December 2011 from five different stations set at Cochin estuary. Water samples from five different stations in Cochin estuary were collected on a monthly basis for a period of two years. Isolates were serotyped, antibiogram-phenotyped for twelve antimicrobial agents, and genotyped by polymerase chain reaction for uid gene that codes for ?-D-glucuronidase. These E. coli strains from Cochin estuary were tested against twelve antibiotics to determine the prevalence of multiple antibiotic resistance among them. The results revealed that more than 53.33% of the isolates were multiple antibiotic resistant. Thirteen isolates showed resistance to sulphonamides and two of them contained the sul 1 gene. Class 1 integrons were detected in two E. coli strains which were resistant to more than seven antibiotics. In the present study, O serotyping, antibiotic sensitivity, and polymerase chain reaction were employed with the purpose of establishing the present distribution of multiple antibiotic-resistant serotypes, associated with E. coli isolated from different parts of Cochin estuary. PMID:23008708

  2. Nitrogenase gene expression in the Chesapeake Bay Estuary.

    PubMed

    Short, Steven M; Zehr, Jonathan P

    2007-06-01

    Like many estuaries, the Chesapeake Bay has pronounced gradients in salinity and nutrients. Previous studies have shown that there is a high diversity of nitrogenase (nifH) genes in the estuary, and that there are specific distributions of individual nifH phylotypes. In contrast to previous work that revealed the remarkable diversity of nifH phylotypes in the Chesapeake estuary, in this study of nifH expression we only detected two phylotypes, and both were phylogenetically related to cyanobacterial nifH genes. One of the phylotypes was closely related to a nifH sequence from the filamentous, heterocystous cyanobacterium Anabaena cylindrica, and was found at the head of the estuary. The other phylotype was found in a sample collected near the mouth of the estuary and was closely related to nifH sequences from Group A unicellular cyanobacteria, which has previously been reported in oceanic waters only. These nifH phylotypes had distinct patterns of expression that were restricted to different regions of the Chesapeake Bay. This study provides the first evidence of nifH expression in the Chesapeake Bay, and suggests that diazotrophic unicellular cyanobacteria have a broader distribution and activity than previously recognized. PMID:17504496

  3. Dissolved Humic Matter in Arctic Estuaries

    NASA Astrophysics Data System (ADS)

    Spitzy, A.; Koehler, H.; Ertl, S.

    2002-12-01

    As part of the German-Russian bilateral SIRRO(Siberian River Runoff)-project we studied the distribution of dissolved humic matter isolated by XAD-8 in the estuarine waters of the Ob and Yenisei rivers. The relative contributions of humic matter carbon to total DOC decreased from 61-77 percent in the river freshwater endmember to 35-40 percent in the marine waters of the open Kara Sea at salinities 33 psu. Humic carbon mixed conservatively in the Yenisei and non-conservatively in the Ob, where partial removal was indicated in the low salinity range. Changes in the relative contribution of humic matter to different molecular weight classes of DOM (ultrafiltration cutoffs 150 KDa, 450 KDa, 800 KDa) were studied along the salinity gradient in the Yenisei. High molecular weight DOM is relatively enriched in humics in fresh-water compared to sea-water HMW-DOM. Low molecular weight DOM is realtively enriched in humics in sea-water compared to fresh-water LMW-DOM. Throughout the estuary humic matter is depleted in 13C and nitrogen compared to total DOM, reflecting a dominant soil source. We estimate an annual input of 5 Tg humic matter carbon by the two rivers into the Kara Sea.

  4. Numerical aerodynamic simulation facility feasibility study

    NASA Technical Reports Server (NTRS)

    1979-01-01

    There were three major issues examined in the feasibility study. First, the ability of the proposed system architecture to support the anticipated workload was evaluated. Second, the throughput of the computational engine (the flow model processor) was studied using real application programs. Third, the availability reliability, and maintainability of the system were modeled. The evaluations were based on the baseline systems. The results show that the implementation of the Numerical Aerodynamic Simulation Facility, in the form considered, would indeed be a feasible project with an acceptable level of risk. The technology required (both hardware and software) either already exists or, in the case of a few parts, is expected to be announced this year. Facets of the work described include the hardware configuration, software, user language, and fault tolerance.

  5. Facilitation of the Estuary/Ocean Subgroup for Federal Research, Monitoring, and Evaluation, FY09 Annual Report

    SciTech Connect

    Johnson, Gary E.

    2009-10-22

    This document is the annual report for fiscal year 2009 (FY09) for the project called Facilitation of the Estuary/Ocean Subgroup (EOS). The EOS is part of the research, monitoring, and evaluation (RME) effort developed by the Action Agencies (Bonneville Power Administration [BPA], U.S. Army Corps of Engineers [Corps or USACE], U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS).

  6. Shallow Sediment Trace Metal Concentrations and Short-Term Accumulation Rates in the Neponset River Estuary, Massachusetts, USA

    Microsoft Academic Search

    J. R. Spencer; J. Zhu; C. R. Olsen

    2010-01-01

    The Neponset River estuary is a small estuary that drains into the Boston Harbor on the east coast of the United States. It is also a highly urbanized estuary and has a long history of urban development over 450 years. In July 2006, six sediment cores were collected in the Neponset River estuary to examine particle dynamics and sediment accumulation

  7. The geomorphology of UK estuaries: The role of geological controls, antecedent conditions and human activities

    NASA Astrophysics Data System (ADS)

    Pye, Kenneth; Blott, Simon J.

    2014-10-01

    This paper provides an overview of the geomorphological characteristics of UK estuaries and the factors which control them. Many of the features included in previous classifications of UK estuaries are not true estuaries since they do not possess significant river influence. The features considered in this paper to be 'true' estuaries are divided into 'restricted entrance' and 'unrestricted entrance' types on the grounds that the size and geometry of the estuary mouth exerts a critical influence on water levels, tidal currents, wave action, sediment transport and morphological evolution. An estuary which has a wide mouth, narrows and becomes shallower towards the head is likely to be flood dominated, especially if it has a large tidal range, whereas an estuary which has a narrow mouth and widens and/or becomes deeper towards the head is more likely to display ebb dominance, especially if it has a relatively small tidal range. Wide-mouthed estuaries are influenced to a greater degree by wave processes than estuaries with a narrow mouth. Previous authors have hypothesised that estuaries may maintain a state of dynamic equilibrium through alternating periods of flood and ebb dominance, but it is concluded that there is presently no substantive evidence to support this hypothesis. UK estuaries have been affected to varying degrees by embanking, land claim, dredging, sea wall breaching and managed realignment. Some estuaries have adjusted quickly to such perturbations, but others continue to show progressive change, either sedimentary infilling or erosion and sediment loss. The quantification of estuary morphometry, identification of change over time, and testing of hypotheses regarding the morphodynamics and stability of estuaries requires adequate bathymetric/topographic, hydrodynamic and sediment data. At present, such data are available for relatively few UK estuaries.

  8. The validation of ecosystem models of turbid estuaries

    NASA Astrophysics Data System (ADS)

    Radford, P. J.; Ruardij, P.

    1987-11-01

    The ecosystem model of the Bristol Channel and Severn Estuary (GEMBASE) was fitted to 3 years of survey data, and has subsequently been validated against a further 5 years of monitoring data. A control chart technique clearly demonstrates that the model is, on the whole, an adequate representation of the estuarine carbon cycle, although the precision of model estimates reduces with increasing trophic level. An ecosystem model of the Ems Estuary has been adapted to simulate the Severn Estuary, and the impact of introducing a notional tidal power scheme assessed. The results were compared to those obtained using GEMBASE in the Severn. The broad predictions from both models are in agreement, although some detail is at variance, which implies that the fundamental ecological assumptions of the models are compatible.

  9. Does boat traffic cause displacement of fish in estuaries?

    PubMed

    Becker, Alistair; Whitfield, Alan K; Cowley, Paul D; Järnegren, Johanna; Næsje, Tor F

    2013-10-15

    Estuaries are increasingly under threat from a variety of human impacts. Recreational and commercial boat traffic in urban areas may represent a significant disturbance to fish populations and have particularly adverse effects in spatially restricted systems such as estuaries. We examined the effects of passing boats on the abundance of different sized fish within the main navigation channel of an estuary using high resolution sonar (DIDSON). Both the smallest (100-300 mm) and largest (>501 mm) size classes had no change in their abundance following the passage of boats. However, a decrease in abundance of mid-sized fish (301-500 mm) occurred following the passage of boats. This displacement may be attributed to a number of factors including noise, bubbles and the rapidly approaching object of the boat itself. In highly urbanised estuarine systems, regular displacement by boat traffic has the potential to have major negative population level effects on fish assemblages. PMID:23938471

  10. Mud transport in the Microtidal San Jacinto Estuary

    NASA Astrophysics Data System (ADS)

    Salehi, M.

    2013-12-01

    The overall objective of this research is to better understand the sediment transport processes in the microtidal San Jacinto Estuary (near Houston, TX) under variable hydrologic conditions. A numerical modeling approach is selected to answer the main question of; how will changes in freshwater input change the sedimentation pattern of the region? In this computational work, no new numerical method or code is developed, but rather an existing technology (MIKE 3D developed by DHI) is used to build a virtual San Jacinto Estuary laboratory where boundary conditions could be applied and altered to the domain to observe the general functional response of the system. Two synthetic freshwater inflows, simulating dry and wet conditions, were used in the numerical modeling experiments. Simulations showed that change in freshwater inflow has major impact on the salinity magnitude within the estuary. In dry conditions, the 5 ppt isohaline traveled all the way upstream of Morgans Point, almost to the confluence of San Jacinto River with Buffalo Bayou. During the extreme wet weather conditions, the 5 ppt isohaline of the surface water was pushed almost as far as Galveston Island. Overall erosion and deposition pattern showed little change between extreme dry and wet years. In general, part of the shallow areas experienced erosion whereas deeper parts of the estuary were under deposition. High freshwater inflow caused around 30% higher deposition in some parts of the channel compared with the low freshwater. Furthermore, examining the mass balance within the whole San Jacinto Estuary showed that around 28% of the input sediment was flushed out during the wet season. But in dry season, not only no sediment left the domain but also it received around 17% of the total available sediment within the estuary from the shelf.

  11. Mud transport in the Microtidal San Jacinto Estuary

    NASA Astrophysics Data System (ADS)

    Salehi, M.; Strom, K. B.

    2012-12-01

    The overall objective of this research is to better understand the sediment transport processes in the microtidal San Jacinto Estuary (near Houston, TX) under variable hydrologic conditions. A numerical modeling approach is selected to answer the main question of; how will changes in freshwater input change the sedimentation pattern of the region? In this computational work, no new numerical method or code is developed, but rather an existing technology (MIKE 3D developed by DHI) is used to build a virtual San Jacinto Estuary laboratory where boundary conditions could be applied and altered to the domain to observe the general functional response of the system. Two synthetic freshwater inflows, simulating dry and wet conditions, were used in the numerical modeling experiments. Simulations showed that change in freshwater inflow has major impact on the salinity magnitude within the estuary. In dry conditions, the 5 ppt isohaline traveled all the way upstream of Morgans Point, almost to the confluence of San Jacinto River with Buffalo Bayou. During the extreme wet weather conditions, the 5 ppt isohaline of the surface water was pushed almost as far as Galveston Island. Overall erosion and deposition pattern showed little change between extreme dry and wet years. In general, part of the shallow areas experienced erosion whereas deeper parts of the estuary were under deposition. High freshwater inflow caused around 30% higher deposition in some parts of the channel compared with the low freshwater. Furthermore, examining the mass balance within the whole San Jacinto Estuary showed that around 28% of the input sediment was flushed out during the wet season. But in dry season, not only no sediment left the domain but also it received around 17% of the total available sediment within the estuary from the shelf.

  12. Water Injection Feasibility for Boeing 747 Aircraft

    NASA Technical Reports Server (NTRS)

    Daggett, David L.

    2005-01-01

    Can water injection be offered at a reasonable cost to large airplane operators to reduce takeoff NO( sub x) emissions? This study suggests it may be possible. This report is a contract deliverable to NASA Glenn Research Center from the prime contractor, The Boeing Commercial Airplane Company of Seattle, WA. This study was supported by a separate contract to the Pratt & Whitney Engine Company of Hartford, CT (contract number NNC04QB58P). Aviation continues to grow and with it, environmental pressures are increasing for airports that service commercial airplanes. The feasibility and performance of an emissions-reducing technology, water injection, was studied for a large commercial airplane (e.g., Boeing 747 with PW4062 engine). The primary use of the water-injection system would be to lower NOx emissions while an important secondary benefit might be to improve engine turbine life. A tradeoff exists between engine fuel efficiency and NOx emissions. As engines improve fuel efficiency, by increasing the overall pressure ratio of the engine s compressor, the resulting increased gas temperature usually results in higher NOx emissions. Low-NO(sub x) combustors have been developed for new airplanes to control the increases in NO(sub x) emissions associated with higher efficiency, higher pressure ratio engines. However, achieving a significant reduction of NO(sub x) emissions at airports has been challenging. Using water injection during takeoff has the potential to cut engine NO(sub x) emissions some 80 percent. This may eliminate operating limitations for airplanes flying into airports with emission constraints. This study suggests an important finding of being able to offer large commercial airplane owners an emission-reduction technology that may also save on operating costs.

  13. Spatial variability of suspended sediment concentration within a tidal marsh in San Francisco Estuary

    NASA Astrophysics Data System (ADS)

    Swanson, K.; Drexler, J. Z.; Schoellhamer, D. H.; Buffington, K.; Takekawa, J.

    2012-12-01

    The sustainability of existing marshes and feasibility of future marsh restoration projects in San Francisco Estuary and elsewhere are threatened by a potential imbalance between accelerating sea-level rise and tidal marsh accretion rates. Marsh accretion is, in large part, dependent upon the availability of suspended sediment supplied from adjacent waterways. As water and sediment move across a marsh plain, suspended sediment settles and is trapped by vegetation near the source, resulting in less suspended-sediment concentration (SSC) and deposition in the interior of the marsh. Measurements of deposition and limited observations of SSC within marshes have confirmed a decrease in sediment supply and accumulation from the marsh edge to the marsh interiors, but the spatial variability of SSC has not been quantified in a manner that allows for comparison to a theoretical sediment transport model. For this study, transects of SSC were collected within a marsh at China Camp State Park in the San Francisco Estuary which demonstrate that a dominant pattern of settling can be quantified and generally matches the exponentially decreasing pattern of SSC predicted by a simple advection-settling model. The observed pattern suggests that sediment settling and marsh flow characteristics are consistent both spatially (between transects) and temporally (between monthly sampling events). However, deviations from the predicted pattern occurred systematically at some locations and are likely related to resuspension of sediment from the marsh surface or small, unmapped creek channels that supply sediment to the marsh. Despite these deviations, our data show this simple 1-D model of advection and settling can be used to generalize within-marsh sediment transport as a function of distance from the nearest sediment source.

  14. Environmental management of a highly impacted, urbanized tropical estuary: rehabilitation and restoration

    NASA Astrophysics Data System (ADS)

    Thorhaug, A.

    1980-03-01

    The principles of the dynamics and interrelationships within the dominant subtropical and tropical Caribbean seagrass community have been studied previously before, during, and after impact. From these and scores of observations of damage and recovery patterns in Thalassia ecosystems, a sense of management recovery strategy has emerged. Artificial restoring of Thalassia testudinum seeds into areas cut off from stock (fruit, seeds) appeared feasible on a large scale after the Turkey Point (Biscayne Bay, Miami, Florida) restoration and test sampling throughout North Biscayne Bay. Two large-scale seeding attempts were made; after 11 months they compared favorably with Turkey Point specimens with regard to growth parameters, despite the turbidity and other persistent pollution. Thus, the possible areas in which Thalassia seed restoration can be used has increased to include estuaries of multiple impact still in various stages of recovery after physical and sewage pollution. This technique should be especially useful to “developing” nations where important nearshore fisheries nurseries based on Thalassia ecosystems have been heavily damaged and now lie barren. Man's impact on the estuary where seed restoration was attempted includes the following activities: 50% of the bay bottom directly dredged or filled (leaving much unconsolidated sediment); 50 million gallons of domestic waste dumped directly into a low flushing part of the bay for 20 years; seven major causeways transecting the bay, restricting circulation and flushing; two artificial inlets made into navigational channels; freshwater sheet flow drastically changed due to channelization by flood-control canals; urban runoff from a million people entering the bay. Most of the impacts have now abated; however, their long-term effects remain.

  15. Alternate shield material feasibility

    SciTech Connect

    Specht, E.R.; Levitt, L.B.

    1984-04-01

    The feasibility and cost/benefit of using materials other than stainless steel for in-vessel neutron shielding in large LMFBRs were investigated. Canned vibratorally compacted B/sub 4/C powder shields were found to be much more economical than stainless steel (a savings of $1.1M in loop plant designs and $9.4M in pool plant designs). The helium gas pressure buildup in B/sub 4/C shields placed around LMFBR in-vessel components (direct reactor heat exchangers in a loop reactor and intermediate heat exchangers in a pool reactor) would only be 0.04 atm after 40 y of reactor operation (with 80% dense powder). The irradiation-induced swelling of the B/sub 4/C would only be 0.002%. No adverse reactor impact would occur if the B/sub 4/C escaped from the B/sub 4/C shields.

  16. Human Impact on Estuaries: A Terrible Spill in Grand Bay

    NSDL National Science Digital Library

    TERC

    2012-07-24

    In this activity, learners make a model of a pollution spill that occurred at Bangs Lake in Mississippi and measure water quality parameters in their model. Learners then study the actual spill, analyzing various forms of data to determine the date of the spill and identify how the spill changed water quality parameters in the estuary during and after the spill. Learners speculate on how various life forms in the estuary were affected. Finally, learners produce a timeline of the spill event, with recommendations to the state Department of Environmental Quality about how to prevent large-scale pollution spills like this in the future.

  17. Impacts of pesticides in a Central California estuary.

    PubMed

    Anderson, Brian; Phillips, Bryn; Hunt, John; Siegler, Katie; Voorhees, Jennifer; Smalling, Kelly; Kuivila, Kathy; Hamilton, Mary; Ranasinghe, J Ananda; Tjeerdema, Ron

    2014-03-01

    Recent and past studies have documented the prevalence of pyrethroid and organophosphate pesticides in urban and agricultural watersheds in California. While toxic concentrations of these pesticides have been found in freshwater systems, there has been little research into their impacts in marine receiving waters. Our study investigated pesticide impacts in the Santa Maria River estuary, which provides critical habitat to numerous aquatic, terrestrial, and avian species on the central California coast. Runoff from irrigated agriculture constitutes a significant portion of Santa Maria River flow during most of the year, and a number of studies have documented pesticide occurrence and biological impacts in this watershed. Our study extended into the Santa Maria watershed coastal zone and measured pesticide concentrations throughout the estuary, including the water column and sediments. Biological effects were measured at the organism and community levels. Results of this study suggest the Santa Maria River estuary is impacted by current-use pesticides. The majority of water samples were highly toxic to invertebrates (Ceriodaphnia dubia and Hyalella azteca), and chemistry evidence suggests toxicity was associated with the organophosphate pesticide chlorpyrifos, pyrethroid pesticides, or mixtures of both classes of pesticides. A high percentage of sediment samples were also toxic in this estuary, and sediment toxicity occurred when mixtures of chlorpyrifos and pyrethroid pesticides exceeded established toxicity thresholds. Based on a Relative Benthic Index, Santa Maria estuary stations where benthic macroinvertebrate communities were assessed were degraded. Impacts in the Santa Maria River estuary were likely due to the proximity of this system to Orcutt Creek, the tributary which accounts for most of the flow to the lower Santa Maria River. Water and sediment samples from Orcutt Creek were highly toxic to invertebrates due to mixtures of the same pesticides measured in the estuary. This study suggests that the same pyrethroid and organophosphate pesticides that have been shown to cause water and sediment toxicity in urban and agriculture water bodies throughout California, have the potential to affect estuarine habitats. The results establish baseline data in the Santa Maria River estuary to allow evaluation of ecosystem improvement as management initiatives to reduce pesticide runoff are implemented in this watershed. PMID:24464329

  18. Information on Estuaries: National Estuarine Research Reserve System

    NSDL National Science Digital Library

    Created by Congress in 1972, the National Estuarine Research Reserve System (NERRS) is dedicated to fostering a system of estuary reserves that represents the wide range of coastal and estuarine habitats found in the United States and its territories. Currently 425,000 acres in 18 states and Puerto Rico are protected by NERRS. Following the brief introduction to estuaries on the homepage is a link to a clickable map of NERRS Sites in the United States. Each NERRS site maintains a homepage with information on the reserves such as the site description, current research, and educational and resource management projects.

  19. Feasibility of remote sensing benthic microalgae

    NASA Technical Reports Server (NTRS)

    Zingmark, R. G.

    1979-01-01

    Results of data analyses from multispectral scanning data are presented. The data was collected in July 1977 for concentration of chlorophyll in benthic microalgae (mainly diatoms) on an estuary mudflat.

  20. Large-scale spatial patterns in estuaries: estuarine macrobenthic communities in the Schelde estuary, NW Europe

    NASA Astrophysics Data System (ADS)

    Ysebaert, T.; Herman, P. M. J.; Meire, P.; Craeymeersch, J.; Verbeek, H.; Heip, C. H. R.

    2003-05-01

    Few macrobenthic studies have dealt simultaneously with the two major gradients in estuarine benthic habitats: the salinity gradient along the estuary (longitudinal) and the gradients from high intertidal to deep subtidal sites (vertical gradient). In this broad-scale study, a large data set (3112 samples) of the Schelde estuary allowed a thorough analysis of these gradients, and to relate macrobenthic species distributions and community structure to salinity, depth, current velocities and sediment characteristics. Univariate analyses clearly revealed distinct gradients in diversity, abundance, and biomass along the vertical and longitudinal gradients. In general, highest diversity and biomass were observed in the intertidal, polyhaline zone and decreased with decreasing salinity. Abundance did not show clear trends and varied between spring and autumn. In all regions, very low values for all measures were observed in the subtidal depth strata. Abundance in all regions was dominated by both surface deposit feeders and sub-surface deposit feeders. In contrast, the biomass of the different feeding guilds showed clear gradients in the intertidal zone. Suspension feeders dominated in the polyhaline zone and showed a significant decrease with decreasing salinity. Surface deposit feeders and sub-surface deposit feeders showed significantly higher biomass values in the polyhaline zone as compared with the mesohaline zone. Omnivores showed an opposite trend. Multivariate analyses showed a strong relationship between the macrobenthic assemblages and the predominant environmental gradients in the Schelde estuary. The most important environmental factor was depth, which reflected also the hydrodynamic conditions (current velocities). A second gradient was related to salinity and confirms the observations from the univariate analyses. Additionally, sediment characteristics (mud content) explained a significant part of the macrobenthic community structure not yet explained by the two other main gradients. The different assemblages are further described in terms of indicator species and abiotic characteristics. The results showed that at a large, estuarine scale a considerable fraction of the variation in abundance and biomass of the benthic macrofauna correlated very well with environmental factors (depth, salinity, tidal current velocity, sediment composition).

  1. Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L.; Ebberts, Blaine D.; Tortorici, Cathy; Yerxa, Tracey; Leary, J.; Skalski, John R.

    2008-02-05

    The purpose ofthis document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision-making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows. 1. Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. 2. Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. 3. Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. 4. Maintain the food web to benefit salmonid performance. 5. Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. In conclusion, the estuary RME effort is designed to meet the research and monitoring needs of the estuary Program using an adaptive management process. Estuary RME's success and usefulness will depend on the actual conduct of adaptive management, as embodied in the objectives, implrementation, data, reporting, and synthesis, evaluation, and decision-making described herein.

  2. The recovery of oyster (Saccostrea glomerata) populations in Sydney estuary (Australia).

    PubMed

    Birch, G F; Scammell, M S; Besley, C H

    2014-01-01

    The current work documented a significant and widespread increase in the abundance of the Sydney rock oyster Saccostrea glomerata, in Sydney estuary (Australia) by undertaking surveys of oyster density in the estuary in 1989 and annually from 1994 to 2006. Oyster density at six control sites located in nearby National Parks unaffected by boating and stormwater discharges were compared to 17 study sites widely distributed within Sydney estuary. No oyster populations were evident in Sydney estuary in 1989; however, by 1994 oysters had colonised areas of the lower and central estuary and by 2002 densities were statistically similar to control sites. The timing of estuary-wide increases in oyster abundance suggests that the partial banning of tributyltin in 1989 for vessels under 25 m long may have played a major role in the increase of S. glomerata in this estuary. PMID:24062067

  3. Tribal Utility Feasibility Study

    SciTech Connect

    Engel, R. A.; Zoellick, J. J.

    2007-06-30

    The Schatz Energy Research Center (SERC) assisted the Yurok Tribe in investigating the feasibility of creating a permanent energy services program for the Tribe. The original purpose of the DOE grant that funded this project was to determine the feasibility of creating a full-blown Yurok Tribal electric utility to buy and sell electric power and own and maintain all electric power infrastructure on the Reservation. The original project consultant found this opportunity to be infeasible for the Tribe. When SERC took over as project consultant, we took a different approach. We explored opportunities for the Tribe to develop its own renewable energy resources for use on the Reservation and/or off-Reservation sales as a means of generating revenue for the Tribe. We also looked at ways the Tribe can provide energy services to its members and how to fund such efforts. We identified opportunities for the development of renewable energy resources and energy services on the Yurok Reservation that fall into five basic categories: • Demand-side management – This refers to efforts to reduce energy use through energy efficiency and conservation measures. • Off-grid, facility and household scale renewable energy systems – These systems can provide electricity to individual homes and Tribal facilities in areas of the Reservation that do not currently have access to the electric utility grid. • Village scale, micro-grid renewable energy systems - These are larger scale systems that can provide electricity to interconnected groups of homes and Tribal facilities in areas of the Reservation that do not have access to the conventional electric grid. This will require the development of miniature electric grids to serve these interconnected facilities. • Medium to large scale renewable energy development for sale to the grid – In areas where viable renewable energy resources exist and there is access to the conventional electric utility grid, these resources can be developed and sold to the wholesale electricity market. • Facility scale, net metered renewable energy systems – These are renewable energy systems that provide power to individual households or facilities that are connected to conventional electric utility grid.

  4. Bin Set 1 Calcine Retrieval Feasibility Study

    SciTech Connect

    R. D. Adams; S. M. Berry; K. J. Galloway; T. A. Langenwalter; D. A. Lopez; C. M. Noakes; H. K. Peterson; M. I. Pope; R. J. Turk

    1999-10-01

    At the Department of Energy's Idaho Nuclear Technology and Engineering Center, as an interim waste management measure, both mixed high-level liquid waste and sodium bearing waste have been solidified by a calculation process and are stored in the Calcine Solids Storage Facilities. This calcined product will eventually be treated to allow final disposal in a national geologic repository. The Calcine Solids Storage Facilities comprise seven ''bit sets.'' Bin Set 1, the first to be constructed, was completed in 1959, and has been in service since 1963. It is the only bin set that does not meet current safe-shutdown earthquake seismic criteria. In addition, it is the only bin set that lacks built-in features to aid in calcine retrieval. One option to alleviate the seismic compliance issue is to transport the calcine from Bin Set 1 to another bin set which has the required capacity and which is seismically qualified. This report studies the feasibility of retrieving the calcine from Bi n Set 1 and transporting it into Bin Set 6 which is located approximately 650 feet away. Because Bin Set 1 was not designed for calcine retrieval, and because of the high radiation levels and potential contamination spread from the calcined material, this is a challenging engineering task. This report presents preconceptual design studies for remotely-operated, low-density, pneumatic vacuum retrieval and transport systems and equipment that are based on past work performed by the Raytheon Engineers and Constructors architectural engineering firm. The designs presented are considered feasible; however, future development work will be needed in several areas during the subsequent conceptual design phase.

  5. The MRIS feasibility study

    NASA Technical Reports Server (NTRS)

    Neece, Robert T.; Cross, Aubrey E.; Schrader, James H.

    1993-01-01

    The Microwave Reflectometer Ionization Sensor (MRIS) is an instrument being developed for use in detecting and ranging of electron density layers in the reentry plasma of a space transfer vehicle. The rationale for the selection of the Double Sideband Suppressed Carrier (DSBSC) system used in the feasibility study for the MRIS is presented. A 25 GHz single-oscillator system and a 220 GHz double-oscillator system are described. The 25 GHz system was constructed and tested in the laboratory and test results are presented. As developed, the system employs a sideband spacing of 160 MHz. Based on an estimated electromagnetic wave velocity in the plasma, a round-trip phase shift measurement accuracy of +/- 7.6 degrees was required for the desired +/- 1/2 cm distance measurement accuracy. The interaction of parallel ground and reflecting planes produces interference that prevents the basic DSBSC system from meeting the accuracy goal so a frequency modulation was added to the system to allow averaging of the measured phase deviation. With an FM deviation of +/- 1 GHz, laboratory measurements were made for distances from 5 to 61 cm tip free space. Accounting for the plasma velocity factor, 82 percent of the data were equal to or better than the desired accuracy. Based on this measured result a sideband spacing to 250 MHz could be expected to yield data approximately 96 percent within the accuracy goal.

  6. Feasibility of advanced fuels

    SciTech Connect

    Momota, Hiromu [National Inst. for Fusion Science, Nagoya (Japan)

    1995-04-01

    Various fusion fuel cycles are reviewed in view of a commercial fusion reactor. Among exothermic fusion reactions, D-{sup 3}He fusion appears attractive because it mitigate engineering problems of DT fusion attributed to 14 MeV neutrons. The safety of the reactor is inherent and environmentally sound with D-{sup 3}He fuelled fusion. Nevertheless, the helium-3 resource is very rare and attempts to breed helium-3 seem unsatisfactory. Lunar helium-3 alone seems to provide the world a needed energy. 8 refs., 4 figs., 1 tab.

  7. Nutrient transport through estuaries: The importance of the estuarine geography

    NASA Astrophysics Data System (ADS)

    Jickells, T. D.; Andrews, J. E.; Parkes, D. J.; Suratman, S.; Aziz, A. A.; Hee, Y. Y.

    2014-10-01

    We consider here first the nature of nutrient transport through estuaries and in particular the capacity of estuaries to modify that flux. We then focus particularly on the Wash system in the UK as an example of a particular type of "small estuary", and also consider some tropical estuarine systems in Malaysia. We present nutrient budgets for the Wash system now and create estimates of these budgets 3000 years ago. These show that currently the system is a small sink for fluvial nitrate (?30% removal) largely due to denitrification and dissolved inorganic phosphorus (?24%) by burial. 3000 years ago, prior to large scale human intervention to reclaim wetlands for agriculture, the Wash system was much bigger and operated as a sink for all terrestrial nitrogen (albeit with much lower inputs) and also a sink for nitrate from the North Sea, predominantly via organic nitrogen burial. A similar change with time is evident in the phosphorus flux. We suggest that this change in function of this estuarine system has been replicated in many other estuarine systems. Given the key role of benthic processes of burial and denitrification we go on to suggest that the classification of estuaries in terms of area and river flow may offer a route to a typology of estuarine nutrient retention efficiency.

  8. ECOLOGICAL CONDITION OF ESTUARIES IN THE GULF OF MEXICO

    EPA Science Inventory

    The Gulf of Mexico is a vast natural resource that encompasses the coastal areas of western Florida, Alabama, Mississippi, Louisiana and Texas, as well as a portion of Mexico. Many estuaries flow into the Gulf of Mexico and serve as nursery grounds for fish, habitat for a wide va...

  9. COASTAL BEND BAYS & ESTUARIES PROGRAM IMPLEMENTATION REVIEW 2004

    EPA Science Inventory

    The Coastal Bend Bays & Estuaries Program, Inc. (CBBEP) is a nonprofit 501(c)(3)organization. The CBBEP project area encompasses 12 counties coincident with the Coastal Bend Council of Governments and extends from the Land-Cut in the Laguna Madre, through the Corpus Christi Bay s...

  10. Production studies in the Mackenzie River — Beaufort Sea estuary

    Microsoft Academic Search

    T. R. Parsons; D. G. Webb; H. Dovey; R. Haigh; M. Lawrence; G. E. Hopky

    1988-01-01

    Production studies were carried out in the Mackenzie River\\/Beaufort Sea estuary during the summer of 1986. Results indicate that there were two plankton communities. One was located near the river mouth and was characterized by high dissolved organic carbon, high bacterial activity and a community of amphipods. The second community was associated with high phytoplankton production off shore and with

  11. SUSCEPTIBILITY OF A NORTHEASTERN GULF OF MEXICO ESTUARY TO HYPOXIA

    EPA Science Inventory

    Bottom water hypoxia is a common adverse consequence of nutrient enrichment in estuaries and coastal waters. To protect against hypoxia, it is helpful to know which waters are most susceptible to hypoxia. Hypoxia has been observed regularly in Pensacola Bay, a northeastern Gulf o...

  12. ANIMAL-HABITAT ASSOCIATIONS IN PACIFIC NORTHWEST ESTUARIES

    EPA Science Inventory

    The mission of the Pacific Coastal Ecology Branch (EPA, Newport, OR) is to determine the effects of habitat alteration by stressors on ecological resources in Pacific Northwest (PNW) estuaries. Research being conducted in support of this mission includes identifying critical hab...

  13. Approaches for Development of Nutrient Criteria in Oregon Estuaries

    EPA Science Inventory

    Development of nutrient criteria for all water body types of the US remains a top priority for EPA. Estuaries in the Pacific Northwest receive nutrients from both the watershed and the coastal ocean, and thus are particularly complex systems in which to establish water quality c...

  14. APPENDIX C - ADDITIONAL INFORMATION ON FLUSHING IN ESTUARIES

    EPA Science Inventory

    Water residence time is an important determinant of the sensitivity of the response of estuaries and other water bodies to nutrient loading. A variety of terms such as residence time, flushing time, transit time, turnover time, and age are used to describe time scales for transpo...

  15. CHEMICAL CARCINOGENS IN BIVALVE MOLLUSKS FROM OREGON ESTUARIES

    EPA Science Inventory

    The research undertaken involved the use of indigenous populatons of bivalve mollusks as monitors for detecting and quantifying environmental benzo(s)pyrene (BAP) in Oregon estuaries. Short-term and long-term studies were conducted in order to establish baseline levels of BAP and...

  16. Polycyclic aromatic hydrocarbons in San Francisco Estuary sediments

    E-print Network

    Polycyclic aromatic hydrocarbons in San Francisco Estuary sediments Daniel R. Oros*, John R.M. Ross pair ratios as indicators showed that PAH are derived primarily from combustion of fossil fuels power plants) with combustion turbines that operate on petroleum distillate fuel and natural gas

  17. MONITORING THE ECOLOGICAL CONDITION OF ESTUARIES IN THE UNITED STATES

    EPA Science Inventory

    The purpose of the Environmental Monitoring and Assessment Program/Estuaries component (EMAP-E) is to determine status, extent, changes, and trends in ecological indicators of the condition of the nation's estuarine resources. onitoring in the Virginian (Mid-Atlantic) and Louisia...

  18. Forward for book entitled "Estuaries: Classification, Ecology, and Human Impacts"

    EPA Science Inventory

    The author was introduced to the science of estuaries as a graduate student in the early 1980s, studying the ecology of oyster populations in Chesapeake Bay. To undertake this research, he needed to learn not only about oyster biology, but also about the unique physical and chemi...

  19. Geochemical processes in the Yenisei River and Estuary

    Microsoft Academic Search

    B. Beeskow; V. Rachold

    2003-01-01

    As a part of the Russian-German project “Siberian River-Runoff (SIRRO)” the major element composition of the dissolved load and the major and trace element composition of particulate load and bottom sediment of the Yenisei River and Estuary were analyzed and examined in context of the basin lithology and climate> In addition, the processes controlling the transformation of the river load

  20. STATISTICAL SUMMARY EMAP-ESTUARIES VIRGINIAN PROVINCE - 1991

    EPA Science Inventory

    Annual monitoring of indicators of the ecological condition of bays and estuaries within the Virginian Province (Cape Cod, MA to Cape Henry, VA) was conducted by the U.S. EPA's Environmental Monitoring and Assessment Program (EMAP) during July, August, and September, 1991. ata we...

  1. FIELD SAMPLING IN ESTUARIES: THE RELATIONSHIP OF SCALE TO VARIABILITY

    EPA Science Inventory

    The spatial/temporal scaling problem (i.e., fitting a given research question to the dimensions of variability of the study area) is particularly pronounced in highly variable systems such as estuaries. Long-term, multidisciplinary studies in the Apalachicola Bay system were used...

  2. Infratidal zonation in a deep South African Estuary

    Microsoft Academic Search

    S. J. M. Blaber; B. J. Hill; A. T. Forbes

    1974-01-01

    The infratidal zonation of animals in a 35 m deep fjord-like South African estuary is described. The barnacle Balanus amphitrite Darwin and the bivalve Musculus virgiliae Barnard form the uppermost zone and extend to a depth of 9 m. The oyster Crassostrea margaritacea (Lam.) forms a zone between 1 and 3 m depth while the sponge Grantessa ramosa (Haeckel) occurs

  3. ROBINSON ESTUARY PRESERVE COASTAL WETLAND HABITAT RESTORATION MX964231

    EPA Science Inventory

    This project will create/enhance approximately 397 acres of habitat in the Robinson Estuary Preserve through wetland creation, transitional and coastal upland enhancement, and exotics control. Section 104(b)(3) of the Clean Water Act will be supported by the proposed project thro...

  4. SEDIMENT MOVEMENT IN THE SALMON RIVER ESTUARY, TRURO, NOVA SCOTIA

    Microsoft Academic Search

    Brad Crewe; Gordon Brewster; Hank Kolstee; Robert Gordon

    This research in the upper reaches of the Bay of Fundy examined the sediment changes occur- ring over two years in a 4.8 km section of the Salmon River Estuary of the Cobequid Bay, at Truro, Nova Scotia. Using water samples collected at the surface during slack tide, the sediment concentration from the water surface downward to a maximum depth

  5. ECOLOGICAL CONDITION OF THE ESTUARIES OF OREGON AND WASHINGTON

    EPA Science Inventory

    Estuaries are bodies of water that receive freshwater and sediment from rivers and saltwater from the oceans. They are transition zones between the fresh water of a river and the salty environment of the sea. This interaction produces a unique environment that supports wildlife...

  6. SAN JUAN BAY ESTUARY, COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN

    EPA Science Inventory

    This Comprehensive Conservation and Management Plan (CCMP) contains information about the overall health of the San Juan Bay Estuary (SJBE) as well as proposed solutions to identified problems. These solutions, or Action Plans, are the result of a more than 4-year process of cons...

  7. UNCORRECTED 2 Iron isotope fractionation in subterranean estuaries

    E-print Network

    of Biological Sciences, University of Southern California, Los Angeles, CA 90089-0371, USA 6 Received 25 April al., 2005; Buck et al., 2007; Ussher et al., 452007). 46The stable isotope composition of Fe canUNCORRECTED PROOF 1 2 Iron isotope fractionation in subterranean estuaries 3 Olivier Rouxel a

  8. ASSESSING THE ECOLOGICAL CONDITION OF VERACRUZ, MX ESTUARIES

    EPA Science Inventory

    As part of an international technology transfer activity between EPA's Office of Research and Development and the state of Veracruz's Sub-secretary of the Environment, 50 stations within estuaries along the gulf coast of the state of Veracruz MX, were sampled during June and July...

  9. ASSESSING THE ECOLOGICAL CONDITION OF VERACRUZ, MEXICO ESTUARIES

    EPA Science Inventory

    Macauley, John, Hector A. Vasquez, George Craven and P. Thomas Heitmuller. In press. Assessing the Ecological Condition of Veracruz, Mexico Estuaries (Abstract). To be presented at the EPA Science Forum: Healthy Communities and Ecosystems, 1-3 June 2004, Washington, DC. 1 p. (ERL...

  10. Mercury bioaccumulation in organisms from three Puerto Rican estuaries

    Microsoft Academic Search

    Joanna Burger; Keith Cooper; Jorge Saliva; D. Gochfeld; D. Lipsky; Michael Gochfeld

    1992-01-01

    We analyzed mercury levels in shrimp (Palaemonetes sp.), Blue Crabs (Callinectes sp.), fish (Tarpon Megalops atlantica and Tilapia Tilapia mossambica), lizards (Ameiva exsul), Cattle Egret (Bubulcus ibis) and Moorhen (Gallinula chloropus) in three estuaries in Puerto Rico in 1988. There were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site.

  11. DAILY STREAMFLOW - VIRGINIA PORTION OF THE ALBEMARLE-PAMLICO ESTUARY

    EPA Science Inventory

    Daily mean discharge data from the U.S. Geological Survey (http://waterdata.usgs.gov/nwis-w/VA) for gaging stations within the Virginia portion of the Albemarle-Pamlico Estuary watershed. Record dates vary by gaging station. Data for each station are located in a text file named ...

  12. PEAK STREAMFLOW - VIRGINIA PORTION OF THE ALBEMARLE-PAMLICO ESTUARY

    EPA Science Inventory

    Peak discharge data from the U.S. Geological Survey (http://waterdata.usgs.gov/nwis-w/VA) for gaging stations within the Virginia portion of the Albemarle-Pamlico Estuary watershed. Record dates vary by gaging station. Data for each station are located in a text file named by sta...

  13. BIVALVES AS BIOMONITORS IN THE NEUSE RIVER AND ESTUARY

    EPA Science Inventory

    In eastern North Carolina the Neuse River and Neuse Estuary have been heavily impacted by the byproducts of row crop and livestock agriculture, forestry operations, and industry as well as effluent from municipal wastewater treatment plants. Non-point pollutants derived from thes...

  14. Radium isotopes in the Orinoco estuary and Eastern Caribbean Sea

    Microsoft Academic Search

    Willard S. Moore; James F. Todd

    1993-01-01

    Radium isotopes provide a means of identifying the source of freshened waters in the ocean and determining the time elapsed since these waters were in the estuary. The authors present evidence that during April, waters from the Amazon mixing zone pass within 50 km of the mouth of the Orinoco River. These Amazon waters are characterized by a lower [sup

  15. AFS Estuaries Section Newsletter Newsletter Editor Lee Benaka

    E-print Network

    . Jane Lubchenco gave about her experience working on the 2003 Pew Oceans Committee Report. When she traveled the country talking to people about oceans, one of their top wishes was to have safe and clean beaches. It's what I dream about all winter. Thank you to all the Estuaries Section members who have

  16. Estuaries May Face Increased Parasitism as Sea Levels Rise

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-12-01

    Invertebrates in estuaries could be at a greater risk of parasitism as climate change causes sea levels to rise. A new paper published 8 December in Proceedings of the National Academy of Sciences of the United States of America (doi:10.1073/pnas.1416747111) describes how rapid sea level rise in the Holocene affected the population of parasitic flatworms called trematodes.

  17. NAME: Port Susan Bay Estuary Restoration LOCATION: Snohomish County, Washington

    E-print Network

    US Army Corps of Engineers

    farmland in the Stillaguamish River estuary in Puget Sound. In doing this, self sustaining native tidal wetlands that support estuarine-dependent animals will be restored, juvenile salmon access to restored at risk salmon species including the following: Chinook salmon and bull trout (ESA Threatened); coho

  18. Impaired health of juvenile Pacific salmon migrating through contaminated estuaries

    Microsoft Academic Search

    T. Collier; M. Arkoosh; E. Casillas; M. Myers; C. Stehr; J. Meador; J. Stein

    2000-01-01

    Juvenile chinook salmon (Oncorhynchus tshawytscha) and chum salmon (Oncorhynchus keta) accumulate polycyclic aromatic hydrocarbons, polychlorinated biphenyls and other chemical contaminants in tissues, fluids and stomach contents while utilizing contaminated estuaries of Puget Sound during their out-migration from fresh water to open ocean. Field studies show that they have impaired health (reduced immunocompetence, increased mortality after disease challenge, reduced growth) resulting

  19. Osmium behavior in estuaries: the Lena River example

    Microsoft Academic Search

    S Levasseur; V Rachold; J.-L Birck; C. J Allègre

    2000-01-01

    The behavior of dissolved osmium at the river\\/ocean interface was studied in the Lena River estuary. Dissolved osmium removal is observed at very low salinities. The loss is estimated to be 28% of the dissolved concentration of the river. The removal cannot be related to the flocculation of iron oxide–organic matter colloids, but occurs simultaneously with the loss of aluminum.

  20. Osmium behavior in estuaries: the Lena River example

    Microsoft Academic Search

    S. Levasseur; V. Rachold; J.-L. Birck; C. J. Allègre

    2000-01-01

    The behavior of dissolved osmium at the river\\/ocean interface was studied in the Lena River estuary. Dissolved osmium removal is observed at very low salinities. The loss is estimated to be 28% of the dissolved concentration of the river. The removal cannot be related to the flocculation of iron oxide-organic matter colloids, but occurs simultaneously with the loss of aluminum.

  1. Estuarine habitat utilization by birds in Yaquina Estuary, Oregon

    EPA Science Inventory

    A wide variety of bird species are highly dependent on intertidal wetland habitats. Because of this dependency, birds are viewed as important indicators of wetland structure and function. Wetlands in Yaquina Bay along with the tidal wetlands in other Pacific coastal estuaries r...

  2. Marine vsFluvial Suspended Matter in the Scheldt Estuary

    NASA Astrophysics Data System (ADS)

    Verlaan, P. A. J.; Donze, M.; Kuik, P.

    1998-06-01

    The ratio of marine to fluvial suspended matter in the Scheldt Estuary was calculated by applying factor analysis to a data set of elemental concentrations. The data set consisted of 98 samples collected under various river discharge conditions. Each sample was analysed for the concentration of Cr, Pb, Fe, Mn, Ni, Co, Ba, Zn, Cu, Cd, S, Ca, Sr, Ag, Sn and Na. Five linearly independent processes were found to describe the variability of the elemental concentrations: (1) the supply of fluvial material to the mixing zone; (2) manganese oxidation in the transition area between the anoxic upper estuary and the oxic lower estuary; (3) the supply of marine material to the mixing zone; (4) a phytoplankton bloom in the lower estuary; and (5) the formation of insoluble metal sulphides in the anoxic high-turbidity zone. Scores of the first and third factor were used to calculate the ratio of marine to fluvial suspended matter in the mixing zone. Information on the origin of both the inorganic and organic fraction of suspended matter was obtained in this way.

  3. SARASOTA BAY NATIONAL ESTUARY PROGRAM, A FRAMEWORK FOR ACTION

    EPA Science Inventory

    Sarasota Bay: Framework for Action was produced by the Sarasota Bay National Estuary Program to characterize the condition of Sarasota Bay and present preliminary options for Bay improvement. The publication is a precursor to the CCMP. Past destruction of sea grasses and mangrove...

  4. IDENTIFYING TOTAL PHOSPHORUS SPECTRAL SIGNAL IN A TROPICAL ESTUARY LAGOON

    E-print Network

    Gilbes, Fernando

    ) this study demonstrates the application of total phosphorus possible spectral indexes to monitor its contentIDENTIFYING TOTAL PHOSPHORUS SPECTRAL SIGNAL IN A TROPICAL ESTUARY LAGOON USING AN HYPERSPECTRAL phosphorus concentrations. A reflectance determination coefficient of 0.49 was obtained from the 467 to 529

  5. ACROCHEMICAL AND NUTRIENT IMPACTS ON ESTUARIES AND OTHER AQUATIC SYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper summarizes the Agrochemical and Nutrient Impacts on Estuaries Symposium held at the 220th American Chemical Society National Meeting. The focus of the symposium was to highlight on-going research efforts to understand estuarine function and pollutant fate in these important ecosystems. E...

  6. BENTHIC NUTRIENT FLUX IN A SMALL ESTUARY IN NORTHWESTERNFLORIDA (USA)

    EPA Science Inventory

    Benthic Nutrient Flux in a Small Estuary in Northwestern Florida(USA).Gulf and Caribbean Research 18, 15-25, 2006. Benthic nutrient fluxes of ammonium (NH4+), nitrite/nitrate (NO2-+NO3-), phosphate (PO4-), and dissolved silica (DSi) were measured in Escambia Bay, an estuar...

  7. Measurements of shoaling internal waves and turbulence in an estuary

    E-print Network

    Kelley, Dan

    . In the deeper part of the study domain, the waves propagated according to the predictions of linear theory losses during propagation [Shroyer et al., 2010a]. Vertical heat flux associated with the wavesMeasurements of shoaling internal waves and turbulence in an estuary Clark Richards,1 Daniel

  8. Measurements of shoaling internal waves and turbulence in an estuary

    E-print Network

    of the study domain, the waves propagated according to the predictions of linear theory. In intermediate losses during propagation [Shroyer et al., 2010a]. Vertical heat flux associated with the wavesMeasurements of shoaling internal waves and turbulence in an estuary Clark Richards,1 Daniel

  9. Physical oceanography of the Río de la Plata Estuary, Argentina

    Microsoft Academic Search

    Raúl A. Guerrero; Eduardo M. Acha; Carlos A. Lasta

    1997-01-01

    The Río de la Plata drains the second largest basin of South America. It flows into the Atlantic Ocean generating an estuarine system of about 35, 000 km2, with only 5–15 m water depth. On the basis of temperature and salinity data from the last 29 years, property seasonality at the estuary were studied. Surface salinity distribution is controlled by

  10. LATITUDINAL GRADIENTS IN BENTHIC COMMUNITY COMPOSITION IN WESTERN ATLANTIC ESTUARIES

    EPA Science Inventory

    The community structure of benthic macroinvertebrates from estuaries along the Atlantic coast of North America from Cape Cod, MA, to Biscayne Bay, FL, were compared. Benthic data were collected over a 5 year period (1990 to 1995) by the U.S. Environmental Protection Agency's Envi...

  11. The tidal asymmetries and residual flows in Ems Estuary

    NASA Astrophysics Data System (ADS)

    Pein, Johannes Ulrich; Stanev, Emil Vassilev; Zhang, Yinglong Joseph

    2014-12-01

    A 3D unstructured-grid numerical model of the Ems Estuary is presented. The simulated hydrodynamics are compared against tidal gauge data and observations from research cruises. A comparison with an idealized test reveals the capability of the model to reproduce the secondary circulation patterns known from theoretical results. The simulations prove to be accurate and realistic, confirming and extending findings from earlier observations and modeling studies. The basic characteristics of dominant physical processes in the estuary such as tidal amplification, tidal damping, overtide generation, baroclinicity and internal mixing asymmetry are quantified. The model demonstrates an overall dominance of the flood currents in most of the studied area. However, the hypsometric control in the vicinity of Dollart Bay reverses this asymmetry, with the ebb currents stronger than the flood ones. Small-scale bathymetric characteristics and baroclinicity result in a very complex interplay between dominant physical mechanisms in different parts of the tidal channels and over the tidal flats. Residual flow reveals a clear overturning circulation in some parts of the estuary which is related to a mixing asymmetry between flood and ebb currents. We demonstrate that while areas close to the tidal river exhibit overall similarity with density controlled estuarine conditions, in large areas of the outer estuary barotropic forcing and complex bathymetry together with the density distribution affect substantially the horizontal circulation.

  12. The Columbia River Estuary the Columbia River Basin

    E-print Network

    a review of the impacts of estuarine conditions on the Council's mission to "protect, mitigate and enhance of the Federal Navigation Channel, and regulation of upper Columbia River flows for hydrosystem needs and flood, our ability to assess impacts of estuarine #12;ISAB 2000-5 Estuary Report ii conditions on the Fish

  13. Invasion by stages in the St Louis River estuary

    EPA Science Inventory

    The St. Louis River estuary is recognized as an invasive species “hotspot” - the harbor ranks among the top locations in the Great Lakes reporting the first occurrence of new, aquatic non-native species. To date, 18 non-native benthic invertebrate, 4 non-native crusta...

  14. Acoustic cloaking in two dimensions: a feasible approach

    Microsoft Academic Search

    Daniel Torrent; José Sánchez-Dehesa

    2008-01-01

    This work proposes an acoustic structure feasible to engineer that accomplishes the requirements of acoustic cloaking design recently introduced by Cummer and Schurig (2007 New J. Phys. 9 45). The structure, which consists of a multilayered composite made of two types of isotropic acoustic metamaterials, exactly matches the conditions for the acoustic cloaking. It is also shown that the isotropic

  15. Feasibility Study on Solid Waste to Energy Technological Aspects

    E-print Network

    Sekhon, Jasjeet S.

    Feasibility Study on Solid Waste to Energy Technological Aspects Yuzhong Tan College of Engineering://www.funginstitute.berkeley.edu/sites/default/ les/SolidWasteToEnergy.pdf April 15, 2013 130 Blum Hall #5580 Berkeley, CA 94720-5580 | (510) 664 seeks to compare and evaluate each technology by reviewing waste to energy reports and seeking

  16. Waste-To-Energy Feasibility Analysis: A Simulation Model

    E-print Network

    Sekhon, Jasjeet S.

    Waste- To- Energy Feasibility Analysis: A Simulation Model Viet- An Duong College of Engineering://www.funginstitute.berkeley.edu/sites/default/ les/WasteToEnergy.pdf May 1, 2014 130 Blum Hall #5580 Berkeley, CA 94720-5580 | (510) 664-4337 | www of the main battles of our generation. Using waste to produce electricity can be a major source of energy

  17. Columbia River Estuary Ecosystem Classification — Concept and application

    USGS Publications Warehouse

    Simenstad, Charles A.; Burke, Jennifer L.; O'Connor, Jim E.; Cannon, Charles; Heatwole, Danelle W.; Ramirez, Mary F.; Waite, Ian R.; Counihan, Timothy D.; Jones, Krista L.

    2011-01-01

    This document describes the concept, organization, and application of a hierarchical ecosystem classification that integrates saline and tidal freshwater reaches of estuaries in order to characterize the ecosystems of large flood plain rivers that are strongly influenced by riverine and estuarine hydrology. We illustrate the classification by applying it to the Columbia River estuary (Oregon-Washington, USA), a system that extends about 233 river kilometers (rkm) inland from the Pacific Ocean. More than three-quarters of this length is tidal freshwater. The Columbia River Estuary Ecosystem Classification ("Classification") is based on six hierarchical levels, progressing from the coarsest, regional scale to the finest, localized scale: (1) Ecosystem Province; (2) Ecoregion; (3) Hydrogeomorphic Reach; (4) Ecosystem Complex; (5) Geomorphic Catena; and (6) Primary Cover Class. We define and map Levels 1-3 for the entire Columbia River estuary with existing geospatial datasets, and provide examples of Levels 4-6 for one hydrogeomorphic reach. In particular, three levels of the Classification capture the scales and categories of ecosystem structure and processes that are most tractable to estuarine research, monitoring, and management. These three levels are the (1) eight hydrogeomorphic reaches that embody the formative geologic and tectonic processes that created the existing estuarine landscape and encompass the influence of the resulting physiography on interactions between fluvial and tidal hydrology and geomorphology across 230 kilometers (km) of estuary, (2) more than 15 ecosystem complexes composed of broad landforms created predominantly by geologic processes during the Holocene, and (3) more than 25 geomorphic catenae embedded within ecosystem complexes that represent distinct geomorphic landforms, structures, ecosystems, and habitats, and components of the estuarine landscape most likely to change over short time periods.

  18. Salinity and turbidity distributions in the Brisbane River estuary, Australia

    NASA Astrophysics Data System (ADS)

    Yu, Yingying; Zhang, Hong; Lemckert, Charles

    2014-11-01

    The Brisbane River estuary (BRE) in Australia not only plays a vital role in ecosystem health, but is also of importance for people who live nearby. Comprehensive investigations, both in the short- and long-term, into the salinity and turbidity distributions in the BRE were conducted. Firstly, the analysis of numerical results revealed that the longitudinal salinity varied at approximately 0.45 and 0.61 psu/h during neap and spring tides, respectively. The turbidity stayed at a higher level and was less impacted by tide in the upper estuary, however, the water cleared up while the tide changed from flood to ebb in the mid and lower estuary. The second investigation into the seasonal variations of salinity and turbidity in the BRE was conducted, using ten-year field measurement data. A fourth-order polynomial equation was proposed, describing the longitudinal variation in salinity dilution changes as the upstream distance in the BRE during the wet and dry seasons. From the observation, the mid and upper estuaries were vertically well-mixed during both seasons, but the lower BRE was stratified, particularly during the wet season. The estuary turbidity maximum (ETM) zone was about 10 km longer during the wet season than the dry season. Particular emphasis was given to the third investigation into the use of satellite remote sensing techniques for estimation of the turbidity level in the BRE. A linear relationship between satellite observed water reflectance and surface turbidity level in the BRE was validated with an R2 of 0.75. The application of satellite-observed water reflectance therefore provided a practical solution for estimating surface turbidity levels of estuarine rivers not only under normal weather conditions, but also during flood events. The results acquired from this study are valuable for further hydrological research in the BRE and particularly prominent for immediate assessment of flood impacts.

  19. Micro electric propulsion feasibility

    NASA Technical Reports Server (NTRS)

    Aston, Graeme; Aston, Martha

    1992-01-01

    Miniature, 50 kg class, strategic satellites intended for extended deployment in space require an on-board propulsion capability to perform needed attitude control adjustments and drag compensation maneuvers. Even on such very small spacecraft, these orbit maintenance functions can be significant and result in a substantial propellant mass requirement. Development of advanced propulsion technology could reduce this propellant mass significantly, and thereby maximize the payload capability of these spacecraft. In addition, spacecraft maneuverability could be enhanced and/or multi-year mission lifetimes realized. These benefits cut spacecraft replacement costs, and reduce services needed to maintain the launch vehicles. For SDIO brilliant pebble spacecraft, a miniaturized hydrazine propulsion system provides both boost and divert thrust control. This type of propulsion system is highly integrated and is capable of delivering large thrust levels for short time periods. However, orbit maintenance functions such as drag make-up require only very small velocity corrections. Using the boost and/or divert thrusters for these small corrections exposes this highly integrated propulsion system to continuous on/off cycling and thereby increases the risk of system failure. Furthermore, since drag compensation velocity corrections would be orders of magnitude less than these thrusters were designed to deliver, their effective specific impulse would be expected to be lower when operated at very short pulse lengths. The net result of these effects would be a significant depletion of the on-board hydrazine propellant supply throughout the mission, and a reduced propulsion system reliability, both of which would degrade the interceptors usefulness. In addition to SDIO brilliant pebble spacecraft, comparably small spacecraft can be anticipated for other future strategic defense applications such as surveillance and communication. For such spacecraft, high capability and reliability, minimal detectability and low cost are requirements. All these miniature spacecraft share a common characteristic: because of their on-board electronic equipment they have, by design, solar order 50-100 W. In a relative sense, such spacecraft are power rich when compared to other larger spacecraft. This power rich situation is offset by very tight mass budgets, which make reductions in propellant mass requirements a key issue in meeting overall spacecraft minimum mass goals. In principle, power rich and propellant poor brilliant pebbles class spacecraft can benefit from using high specific impulse electric propulsion to reduce chemical propellant mass requirements. However, at power levels of order 50 W, arcjets cannot be made to function, ion thrusters are too complex and heavy and resistojets have too low a specific impulse. Recognizing these capability limitations in existing electric propulsion technology, the SDIO/IST sponsored the Phase I SBIR Micro Electric Propulsion (MEP) thruster study described in this report. The objective of this study was to examine the feasibility of developing a very simple, low mass and small volume, electric thruster for operation on hydrazine at less than 100 W of input power. The feasibility of developing such a MEP thruster was successfully demonstrated by EPL by the discovery of a novel plasma acceleration process. The sections in this report summarize the approach, test results and major accomplishments of this proof-of-concept program.

  20. Ceramic automotive Stirling engine program

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The Ceramic Automotive Stirling Engine Program evaluated the application of advanced ceramic materials to an automotive Stirling engine. The objective of the program was to evaluate the technical feasibility of utilizing advanced ceramics to increase peak engine operating temperature, and to evaluate the performance benefits of such an increase. Manufacturing cost estimates were also developed for various ceramic engine components and compared with conventional metallic engine component costs.

  1. Ceramic Automotive Stirling Engine Program

    SciTech Connect

    Not Available

    1986-08-01

    The Ceramic Automotive Stirling Engine Program evaluated the application of advanced ceramic materials to an automotive Stirling engine. The objective of the program was to evaluate the technical feasibility of utilizing advanced ceramics to increase peak engine operating temperature, and to evaluate the performance benefits of such an increase. Manufacturing cost estimates were also developed for various ceramic engine components and compared with conventional metallic engine component costs.

  2. Residual fluxes of suspended sediment in a tidally dominated tropical estuary

    NASA Astrophysics Data System (ADS)

    Schettini, Carlos Augusto França; Duarte Pereira, Marçal; Siegle, Eduardo; de Miranda, Luiz Bruner; Silva, Mário P.

    2013-11-01

    This paper assesses the fine sediment fluxes in the Caravelas estuarine system (Bahia, Brazil, 17o45'S and 039o12'W). The estuary reaches the ocean at the shore across from the Abrolhos Bank, the largest tropical reef habitat in the South Atlantic. The Caravelas estuarine system is composed of several meandering channels, which are connected to the ocean by a double inlet system. These two openings - the Caravelas and Nova Viçosa estuaries - are connected by a narrow, 30 km long channel. The Caravelas estuary does not receive significant continental input, while the Nova Viçosa estuary receives the contribution of the Peruíbe River, which drains an area of approximately 5000 km2. To understand the fine sediment dynamics and net transport, observations of tides, currents, salinity and suspended sediment concentration (SSC) were recorded in 13-h tidal surveys (spring and neap tide) and with 20-day long CTDs/ADCP moorings at the Caravelas estuary and in the interconnection channel. The SSC dynamic in the Caravelas estuary is primarily driven by advection, with SSC originating in the inlet and inner shelf area. Residual water and sediment transport are up-estuary in the Caravelas estuary and toward the Caravelas estuary in the interconnection channel. The residual transport showed pronounced synodical modulation and was stronger during spring tide. The Caravelas estuary function as a trap for inner shelf materials and fine sediments delivered by the Peruípe River at Nova Viçosa.

  3. Morphodynamic evolution of the Xiaoqing River mouth: a Huanghe River-derived mixed energy estuary

    NASA Astrophysics Data System (ADS)

    Huang, Haijun; Liu, Yanxia; Qiu, Zhongfeng

    2012-09-01

    In an estuary, tidal, wave and other marine powers interact with the coast in different ways and affect estuary morphology as well as its evolution. In the Huanghe (Yellow) River estuaries and nearby delta, there are many small sediment-affected estuaries with a unique morphology, such as the Xiaoqing River estuary. In this study, we investigated the special evolution and genetic mechanism of the Xiaoqing River estuary by analyzing graphic and image data with a numerical simulation method. The results show that NE and NE-E tide waves are the main driving force for sandbar formation. Sediment shoals have originated from huge amounts of sediment from the Huanghe River, with consequent deposition at the Xiaoqing River mouth. The lateral suspended sediments beyond the river mouth move landward. Siltation takes place on the northern shoreline near the river mouth whereas erosion occurs in the south. The deposits come mainly from scouring of the shallow seabed on the northern side of the estuary. Storm surges speed up deposition in the estuary. Development of the sediment shoals has occurred in two steps involving the processes of growth and further southward extension. Although the southward shift increases the river curvature and length, the general eastward orientation of the estuary is unlikely to change. Processes on the adjacent shorelines do not affect the development of the sediment shoals. The study presents a morphodynamic evolutionary model for the Xiaoqing River estuary, with a long-term series cycle, within which a relatively short cycle occurs.

  4. Temporal changes in physical, chemical and biological sediment parameters in a tropical estuary after mangrove deforestation

    NASA Astrophysics Data System (ADS)

    Ellegaard, Marianne; Nguyen, Ngoc Tuong Giang; Andersen, Thorbjørn Joest; Michelsen, Anders; Nguyen, Ngoc Lam; Doan, Nhu Hai; Kristensen, Erik; Weckström, Kaarina; Son, Tong Phuoc Hoang; Lund-Hansen, Lars Chresten

    2014-04-01

    Dated sediment cores taken near the head and mouth of a tropical estuary, Nha-Phu/Binh Cang, in south central Viet Nam were analyzed for changes over time in physical, chemical and biological proxies potentially influenced by removal of the mangrove forest lining the estuary. A time-series of satellite images was obtained, which showed that the depletion of the mangrove forest at the head of the estuary was relatively recent. Most of the area was converted into aquaculture ponds, mainly in the late 1990's. The sediment record showed a clear increase in sedimentation rate at the head of the estuary at the time of mangrove deforestation and a change in diatom assemblages in the core from the mouth of the estuary indicating an increase in the water column turbidity of the entire estuary at the time of the mangrove deforestation. The proportion of fine-grained sediment and the ?13C signal both increased with distance from the head of the estuary while the carbon content decreased. The nitrogen content and the ?15N signal were more or less constant throughout the estuary. The proportion of fine-grained material and the chemical proxies were more or less stable over time in the core from the mouth while they varied synchronously over time in the core from the head of the estuary. The sediment proxies combined show that mangrove deforestation had large effects on the estuary with regard to both the physical and chemical environment with implications for the biological functioning.

  5. Building Regional Threat-Based Networks for Estuaries in the Western United States

    PubMed Central

    Merrifield, Matthew S.; Hines, Ellen; Liu, Xiaohang; Beck, Michael W.

    2011-01-01

    Estuaries are ecologically and economically valuable and have been highly degraded from both land and sea. Estuarine habitats in the coastal zone are under pressure from a range of human activities. In the United States and elsewhere, very few conservation plans focused on estuaries are regional in scope; fewer still address threats to estuary long term viability.We have compiled basic information about the spatial extent of threats to identify commonalities. To do this we classify estuaries into hierarchical networks that share similar threat characteristics using a spatial database (geodatabase) of threats to estuaries from land and sea in the western U.S.Our results show that very few estuaries in this region (16%) have no or minimal stresses from anthropogenic activity. Additionally, one quarter (25%) of all estuaries in this study have moderate levels of all threats. The small number of un-threatened estuaries is likely not representative of the ecological variability in the region and will require working to abate threats at others. We think the identification of these estuary groups can foster sharing best practices and coordination of conservation activities amongst estuaries in any geography. PMID:21387006

  6. GIS as a Tool for Integrated Studies of Dynamic Processes of Estuaries: An Example From the Hudson River Estuary

    Microsoft Academic Search

    C. Bertinato; F. O. Nitsche; W. B. Ryan; S. M. Carbotte; R. Bell

    2002-01-01

    Estuaries are the subject of many different processes which are often complex and interdependent. This includes sediment transport, hydrology, biological habitats and human activities. It is often difficult to link these processes together, but because they are linked to each other looking at many of these aspects are often essential for obtaining useful results. Modern Geographic Information Systems (GIS) can

  7. Feeding preferences of estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus in a temperate estuary (Guadalquivir Estuary, SW Spain)

    NASA Astrophysics Data System (ADS)

    Vilas, César; Drake, Pilar; Fockedey, Nancy

    2008-04-01

    Mysid shrimps are an important component of estuarine food webs because they play a key role in energy transfer as intermediate prey. We investigated the seasonal, tidal and depth specific variation in the diet of the estuarine mysids Neomysis integer and Rhopalophthalmus tartessicus and explored its implications for the planktonic community structure of a temperate estuary (Guadalquivir Estuary, SW Spain). Neomysis integer is an opportunistic omnivore feeding mainly on mesozooplankton and on members of the detrital-microbial loop, shifting prey seasonally according to availability. In contrast, R. tartessicus showed a more carnivorous diet and shifted its target prey during seasons of low resource availability. Despite statistically significant differences in diet composition, both species shared prey of similar size, particularly juvenile Mesopodopsis slabberi, the most abundant mysid species in this estuary, and copepods. Although these similarities imply inter-specific resource competition, their co-existence is achieved by niche partitioning and spatial segregation: the higher osmoregulatory capacity and foraging plasticity of N. integer confers a broader niche breadth for this species allowing N. integer to inhabit the more stressful oligohaline region of the estuary where R. tartessicus cannot survive. We propose that this mechanism relaxes the potential for competition between N. integer and R. tartessicus.

  8. Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2009

    SciTech Connect

    Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.; Dawley, Earl M.; Coleman, Andre M.

    2010-08-01

    This report describes the 2009 research conducted under the U.S. Army Corps of Engineers (USACE or Corps) project EST-09-P-01, titled “Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary.” The research was conducted by the Pacific Northwest National Laboratory, Marine Science Laboratory and Hydrology Group, in partnership with the University of Washington, School of Aquatic and Fishery Sciences, Columbia Basin Research, and Earl Dawley (NOAA Fisheries, retired). This Columbia River Fish Mitigation Program project, referred to as “Salmonid Benefits,” was started in FY 2009 to evaluate the state-of-the science regarding the ability to quantify the benefits to listed salmonids1 of habitat restoration actions in the lower Columbia River and estuary.

  9. Modeling ecosystem processes with variable freshwater inflow to the Caloosahatchee River Estuary, southwest Florida. I. Model development

    NASA Astrophysics Data System (ADS)

    Buzzelli, Christopher; Doering, Peter H.; Wan, Yongshan; Sun, Detong; Fugate, David

    2014-12-01

    Variations in freshwater inflow have ecological consequences for estuaries ranging among eutrophication, flushing and transport, and high and low salinity impacts on biota. Predicting the potential effects of the magnitude and composition of inflow on estuaries over a range of spatial and temporal scales requires reliable mathematical models. The goal of this study was to develop and test a model of ecosystem processes with variable freshwater inflow to the sub-tropical Caloosahatchee River Estuary (CRE) in southwest Florida from 2002 to 2009. The modeling framework combined empirically derived inputs of freshwater and materials from the watershed, daily predictions of salinity, a box model for physical transport, and simulation models of biogeochemical and seagrass dynamics. The CRE was split into 3 segments to estimate advective and dispersive transport of water column constituents. Each segment contained a sub-model to simulate changes in the concentrations of organic nitrogen and phosphorus (ON and OP), ammonium (NH4+), nitrate-nitrite (NOx-), ortho-phosphate (PO4-3), phytoplankton chlorophyll a (CHL), and sediment microalgae (SM). The seaward segment also had sub-models for seagrasses (Halodule wrightii and Thalassia testudinum). The model provided realistic predictions of ON in the upper estuary during wet conditions since organic nitrogen is associated with freshwater inflow and low salinity. Although simulated CHL concentrations were variable, the model proved to be a reliable predictor in time and space. While predicted NOx- concentrations were proportional to freshwater inflow, NH4+ was less predictable due to the complexity of internal cycling during times of reduced freshwater inflow. Overall, the model provided a representation of seagrass biomass changes despite the absence of epiphytes, nutrient effects, or sophisticated translocation in the formulation. The model is being used to investigate the relative importance of colored dissolved organic matter (CDOM) vs. CHL in submarine light availability throughout the CRE, assess if reductions in nutrient loads are more feasible by controlling freshwater quantity or N and P concentrations, and explore the role of inflow and flushing on the fates of externally and internally derived dissolved and particulate constituents.

  10. An engine air-brake integration study

    E-print Network

    Mulchandani, Hiten

    2011-01-01

    The feasibility of operating an engine air-brake (EAB) integrated with a pylon duct bifurcation in a realistic aircraft engine environment has been analyzed. The EAB uses variable exit guide vanes downstream of a high ...

  11. Assessment on vulnerability of coastal wetlands to sea level rise in the Yangtze Estuary, China

    NASA Astrophysics Data System (ADS)

    Cui, L.; Ge, Z.; Zhang, L.

    2013-12-01

    The Yangtze Delta in China is vital economic hubs in terms of settlement, industry, agriculture, trade and tourism as well as of great environmental significance. In recent decades, the prospect of climate change, in particular sea level rise and its effects on low lying coastal areas have generated worldwide attention to coastal ecosystems. Coastal wetlands, as important parts of coastal ecosystem, are particularly sensitive to sea level rise. To study the responses of coastal wetlands to climate change, assess the impacts of climate change on coastal wetlands and formulate feasible and practical mitigation strategies are the important prerequisites for securing the coastal zone ecosystems. In this study, taking the coastal wetlands in the Yangtze Estuary as a case study, the potential impacts of sea-level rise to coastal wetlands habitat were analyzed by the Source-Pathway-Receptor-Consequence (SPRC) model. The key indicators, such as the sea-level rise rate, subsidence rate, elevation, daily inundation duration of habitat and sedimentation rate, were selected to build a vulnerability assessment system according to the IPCC definition of vulnerability, i.e. the aspects of exposure, sensitivity and adaptation. A quantitatively spatial assessment method on the GIS platform was established by quantifying each indicator, calculating the vulnerability index and grading the vulnerability. The vulnerability assessment on the coastal wetlands in the Yangtze Estuary under the sea level rise rate of the present trend and IPCC A1F1 scenario were performed for three sets of projections of short-term (2030s), mid-term (2050s) and long-term (2100s). The results showed that at the present trend of sea level rise rate of 0.26 cm/a, 92.3 % of the coastal wetlands in the Yangtze Estuary was in the EVI score of 0 in 2030s, i.e. the impact of sea level rise on habitats/species of coastal wetlands was negligible. While 7.4 % and 0.3 % of the coastal wetlands were in the EVI score of 1(low vulnerability) and 2 (moderate vulnerability), respectively. In 2050s, 88.8 %, 10.7 % and 0.5 % of the coastal wetlands were in the EVI score of 0, 1 and 2, respectively. In 2100s, 85.7 %, 7.3 % , 2.0 % and 5.0 % of the coastal wetlands were in the EVI score of 0, 1, 2 and 3(high vulnerability), respectively. At the A1F1 scenario of sea level rise rate of 0.59 cm/a, 91.0 %, 8.7 % and 0.3 % of the coastal wetlands in 2030s were in the EVI score of 0, 1 and 2 , respectively. In 2050s, 86.9 %, 10.5 % , 2.4 % and 0.2 % of the coastal wetlands were in the EVI score of 0, 1, 2 and 3, respectively. In 2100s, 82.4 %, 7.1 % , 2.4 % and 8.1 % of the coastal wetlands were in the EVI score of 0, 1, 2 and 3, respectively. The spatiotemporal occurrences of vulnerability were mainly where the subsidence rate is relatively higher and the sedimentation rate is lower or even negative. The results from this study indicated that the combined effects of sea level rise, land subsidence, reducing sediment discharge could give rise to the high risk of a considerable decrease or even habitat loss of coastal wetland in the Yangtze Estuary (particularly in 2050s and 2100s). Therefore some mitigation measures should be considered in the future, including management of sedimentation, reducing land subsidence, recreating and extending wetland habitat, and controlling reclamation.

  12. Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States. (UNH)

    EPA Science Inventory

    The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

  13. Estuary Data Mapper: A Stand-Alone Tool for Geospatial Data Access, Visualization and Download for Estuaries and Coastal Watersheds of the United States

    EPA Science Inventory

    The US EPA Estuary Data Mapper (EDM; http://badger.epa.gov/rsig/edm/index.html) has been designed as a free stand-alone tool for geospatial data discovery, visualization, and data download for estuaries and their associated watersheds in the conterminous United States. EDM requi...

  14. Freeport Harbor, Texas, Channel Improvement Project Feasibility Report and Environmental Impact Statement

    E-print Network

    US Army Corps of Engineers

    ) and Environmental Impact Statement (EIS). The Battelle IEPR panel reviewed the Draft Feasibility Report (DFR Impact Statement U.S. Army Corps of Engineers Response to Independent External Peer Review October 2012#12;1 Freeport Harbor, Texas, Channel Improvement Project Feasibility Report and Environmental

  15. Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program.

    SciTech Connect

    Johnson, Gary E.; Diefenderfer, Heida L. (Pacific Northwest National Laboratory)

    2008-02-20

    The purpose of this document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program, hereafter called 'the Estuary Program'. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows: (1) Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. (2) Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. (3) Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. (4) Maintain the food web to benefit salmonid performance. (5) Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. The goal leads to three primary management questions pertaining to the main focus of the Estuary Program: estuary habitat conservation and restoration. (1) Are the estuary habitat actions achieving the expected biological and environmental performance targets? (2) Are the offsite habitat actions in the estuary improving juvenile salmonid performance and which actions are most effective at addressing the limiting factors preventing achievement of habitat, fish, or wildlife performance objectives? (3) What are the limiting factors or threats in the estuary/ocean preventing the achievement of desired habitat or fish performance objectives? Performance measures for the estuary are monitored indicators that reflect the status of habitat conditions and fish performance, e.g., habitat connectivity, survival, and life history diversity. Performance measures also pertain to implementation and compliance. Such measures are part of the monitoring, research, and action plans in this estuary RME document. Performance targets specific to the estuary were not included in the 2007 draft Biological Opinion.

  16. A review of solar-powered Stirling engines and low temperature differential Stirling engines

    Microsoft Academic Search

    Bancha Kongtragool; Somchai Wongwises

    2003-01-01

    This article provides a literature review on solar-powered Stirling engines and low temperature differential Stirling engines technology. A number of research works on the development of Stirling engines, solar-powered Stirling engines, and low temperature differential Stirling engines is discussed. The aim of this review is to find a feasible solution which may lead to a preliminary conceptual design of a

  17. Multnomah County Hydrokinetic Feasibility Study: Final Feasibility Study Report

    SciTech Connect

    Stephen Spain

    2012-03-15

    HDR has completed a study of the technical, regulatory, and economic feasibility of installing hydrokinetic turbines under the Morrison, Broadway, and Sellwood bridges. The primary objective of installing hydrokinetic turbines is a demonstration of in-stream hydrokinetic technologies for public education and outreach. Due to the low gradient of the Lower Willamette and the effects of the tide, velocities in the area in consideration are simply not high enough to economically support a commercial installation. While the velocities in the river may at times provide enough energy for a commercial turbine to reach capacity, the frequency and duration of high flow events which provide suitable velocities is not sufficient to support a commercial hydrokinetic installation. We have observed that over an 11 year period, daily average velocities in the Lower Willamette exceeded a nominal cut-in speed of 0.75 m/s only 20% of the time, leaving net zero power production for the remaining 80% of days. The Sellwood Bridge site was estimated to have the best hydrokinetic resource, with an estimated average annual production of about 9,000 kWh. The estimated production could range from 2,500 kWh to 15,000 kWh. Based on these energy estimates, the amount of revenue generated through either a power purchase agreement (PPA) or recovered through net metering is not sufficient to repay the project costs within the life of the turbine. The hydrokinetic resource at the Morrison and Broadway Bridges is slightly smaller than at the Sellwood Bridge. While the Broadway and Morrison Bridges have existing infrastructure that could be utilized, the project is not expected to generate enough revenue to repay the investment. Despite low velocities and energy production, the sites themselves are favorable for installation of a demonstration or experimental project. With high public interest in renewable energy, the possibility exists to develop a hydrokinetic test site which could provide developers and scientists a location to temporarily deploy and test hydrokinetic devices, and also function as an educational tool for the general public. Bridge piers provide an excellent pre-existing anchor point for hydrokinetic devices, and existing infrastructure at the Morrison and Broadway Bridges may reduce installation costs. Opportunity exists to partner with local universities with engineering and environmental interest in renewable energy. A partnership with Portland State University�¢����s engineering school could provide students with an opportunity to learn about hydrokinetics through senior design projects. Oregon State University and University of Washington, which are partnered through the Northwest National Marine Renewable Energy Center (NNMREC) to study and test hydrokinetic technology, are also relatively local to the site. In addition to providing an opportunity for both public and private entities to learn technically about in-stream kinetics, this approach will encourage grant funding for outreach, education, and product development, while also serving as a positive community relations opportunity for the County and its partners.

  18. The role of tides in redistributing macrodetrital aggregates within the Swartvlei estuary

    Microsoft Academic Search

    Alan K. Whitfield

    1988-01-01

    The Swartvlei estuary possesses a prolific growth of both intertidal and subtidal eelgrass,Zostera capensis. During 1984 less than 12% of the eelgrass beds were located in the upper half of the estuary, yet deposition ofZostera\\/macroalgal wrack in this region, when the estuary was linked to the sea (open phase), was similar to that in the lower half.\\u000a Over a period

  19. Physicochemical and environmental characterisation of sediments from Cantabrian estuaries (Northern Spain)

    Microsoft Academic Search

    A. Coz; C. González-Piñuela; A. Andrés; J. R. Viguri

    2007-01-01

    Previous studies show that sediments of the Cantabrian estuaries (Northern Spain) contain significant concentrations of heavy metals and organic pollutants derived from intensive industrial, agricultural and urban activities. In the most polluted sediments of two estuaries (the bay of Santander and estuary of Suances), physico-chemical and environmental characterisation has been carried out.Water content, density, pH, specific surface, porosity and particle

  20. Phylogeography of the copepod Acartia hudsonica in estuaries of the northeastern United States

    Microsoft Academic Search

    Peter J. Milligan; Eli A. Stahl; Nikolaos V. Schizas; Jefferson T. Turner

    2011-01-01

    Copepods of the genus Acartia dominate zooplankton assemblages in northwestern Atlantic estuaries, many of which originated after the last glacial maximum\\u000a 10,000–18,000 years ago. Acartia hudsonica occurs, at least seasonally, in estuaries from Chesapeake Bay to Labrador\\/Newfoundland. We sequenced the mitochondrial gene\\u000a Cytochrome B (CytB) of 75 individuals of A. hudsonica from 26 estuaries from New Jersey to Maine, covering four

  1. WERF MACT Feasibility Study Report

    SciTech Connect

    B. Bonnema; D. Moser; J. Riedesel; K. Kooda; K. Liekhus; K. Rebish; S. Poling

    1998-11-01

    This study was undertaken to determine the technical feasibility of upgrading the Waste Experimental Reduction Facility (WERF) at the Idaho National Engineering and Environmental Laboratory to meet the offgas emission limits proposed in the Maximum Achievable Control Technologies (MACT)rule. Four practicable offgas treatment processes were identified, which, if installed, would enable the WERF to meet the anticipated MACT emission limits for dioxins and furans (D/F), hydrochloric acid (HCI), and mercury (Hg). Due to the three-year time restraint for MACT compliance, any technology chosen for the upgrade must be performed within the general plant project funding limit of $5 M. The option selected consists of a partial-quench evaporative cooler with dry sorbent injection for HCI removal followed by a sulfur-impregnated activated carbon bed for Hg control. The planning cost estimate for implementing the option is $4.17 M (with 24% contingency). The total estimated cost includes capital costs, design and construction costs, and project management costs. Capital costs include the purchase of a new offgas evaporative cooler, a dry sorbent injection system with reagent storage, a new fabric filter baghouse, a fixed carbon bed absorber, and two offgas induced draft exhaust fans. It is estimated that 21 months will be required to complete the recommended modification to the WERF. The partial-quench cooler is designed to rapidly cool the offgas exiting the secondary combustion chamber to minimize D/F formation. Dry sorbent injection of an alkali reagent into the offgas is recommended. The alkali reacts with the HCI to form a salt, which is captured with the fly ash in the baghouse. A design HCI removal efficiency of 97.2% allows for the feeding 20 lbs/hr of chlorine to the WERF incinerator. The sorbent feed rate can be adjusted to achieve the desired HCI removal efficiency. A fixed bed of sulfur-impregnated carbon was conservatively sized for a total Hg removal capacity when feeding 10 g/hr Hg to the WERF incinerator. An added benefit for using carbon adsorption is that the activated carbon will also capture a large fraction of any residual D/F present in the offgas.

  2. (Feasibility study of the San Lorenzo River hydroelectric project)

    SciTech Connect

    Chronowski, R.A.

    1990-07-19

    I travelled to San Jose, Costa Rica on July 8, 1990 to evaluate all of the completed elements of the ongoing feasibility study for the San Lorenzo River hydroelectric project. The feasibility study is being supported by ORNL under the Renewable Energy Applications and Training Project. The project is being studied for implementation by CONELECTRICAS, a consortium of rural electric cooperatives and the study itself is being conducted by BEL Engineering, a Costa Rican consulting firm under contract to CONELECTRICAS, USAID/PIC and NRECA.

  3. Where river and tide meet: The morphodynamic equilibrium of alluvial estuaries

    NASA Astrophysics Data System (ADS)

    Bolla Pittaluga, Michele; Tambroni, Nicoletta; Canestrelli, Alberto; Slingerland, Rudy; Lanzoni, Stefano; Seminara, Giovanni

    2015-01-01

    We investigate the morphodynamic equilibrium of tidally dominated alluvial estuaries, extending previous works concerning the purely tidal case and the combined tidal-fluvial case with a small tidal forcing. We relax the latter assumption and seek the equilibrium bed profile of the estuary, for a given planform configuration with various degrees of funneling, solving numerically the 1-D governing equation. The results show that with steady fluvial and tidal forcings, an equilibrium bed profile of estuaries exists. In the case of constant width estuaries, a concave down equilibrium profile develops through most of the estuary. Increasing the amplitude of the tidal oscillation, progressively higher bed slopes are experienced at the mouth while the river-dominated portion of the estuary experiences an increasing bed degradation. The fluvial-marine transition is identified by a "tidal length" that increases monotonically as the river discharge and the corresponding sediment supply are increased while the river attains a new morphological equilibrium configuration. Tidal length also increases if, for a fixed river discharge and tidal amplitude, the sediment flux is progressively reduced with respect to the transport capacity. In the case of funnel-shaped estuaries the tidal length strongly decreases, aggradation is triggered by channel widening, and tidal effects are such to enhance the slope at the inlet and the net degradation of the river bed. Finally, results suggest that alluvial estuaries in morphological equilibrium cannot experience any amplification of the tidal wave propagating landward. Hence, hypersynchronous alluvial estuaries cannot be in equilibrium.

  4. Using a multi-component indicator toward reducing phytoplankton bloom occurrences in the Swan River estuary.

    PubMed

    Kristiana, Ria; Antenucci, Jason P; Imberger, Jorg

    2012-08-01

    The Swan River estuary is an icon of the city of Perth, Western Australia, running through the city centre and dividing the northern from the southern part of the city. However, frequent phytoplankton blooms have been observed in the estuary as a result of eutrophication. The Index of Sustainable Functionality (ISF), a composite index able to indicate for sustainable health of the estuary, was applied, taking into account the hydrology and highly seasonal nature of the estuary to inform the management of the estuary, towards the aim of reducing bloom occurrences. The study period was from the beginning of intensive monitoring in 1995 to mid-2009. The results emphasize the importance of physical controls on the ecology of the estuary. No significant trend in the estuary's low functionality was found, indicating that despite extensive restoration efforts, the frequency of algal bloom occurrences has remained relatively stationary and other mitigating factors have maintained an annual average ISF value at around 70 % functionality. We identified that the low flow season consistently performs the worst, with (high) temperature found as the most dominant variable for phytoplankton growth and bloom. Thus in managing the estuary, vigilance is required during periods of high temperature and low flow. Focusing on the risk of phytoplankton bloom, a nutrient reduction program that is in place is a long term solution due to high concentrations in the estuary. Other management measures need to be considered and adopted to effectively reduce the occurrences of future phytoplankton blooms. PMID:22669343

  5. Distribution and sources of particulate organic matter in the Indian monsoonal estuaries during monsoon

    NASA Astrophysics Data System (ADS)

    Sarma, V. V. S. S.; Krishna, M. S.; Prasad, V. R.; Kumar, B. S. K.; Naidu, S. A.; Rao, G. D.; Viswanadham, R.; Sridevi, T.; Kumar, P. P.; Reddy, N. P. C.

    2014-11-01

    The distribution and sources of particulate organic carbon (POC) and nitrogen (PN) in 27 Indian estuaries were examined during the monsoon using the content and isotopic composition of carbon and nitrogen. Higher phytoplankton biomass was noticed in estuaries with deeper photic zone than other estuaries receiving higher suspended matter. The ?13CPOC and ?15NPN data suggest that relatively higher ?13CPOC (-27.9 to -22.6‰) and lower ?15NPN (0.7 to 5.8‰) were noticed in the estuaries located in the northern India, north of 16°N, and lower ?13CPOC (-31.4 to -28.2‰) and higher ?15NPN (5 to 10.3‰) in the estuaries located in the southern India. This is associated with higher Chl a in the northern than southern estuaries suggesting that in situ production contributed significantly to the POC pool in the former, whereas terrestrial sources are important in the latter estuaries. The spatial distribution pattern of ?15NPN is consistent with fertilizer consumption in the Indian subcontinent, which is twice as much in the northern India as in the south whereas ?13CPOC suggests that in situ production is a dominant source in the southern and terrestrial sources are important in the northern estuaries. Based on the Stable Isotope Analysis in R model, 40-90% (70-90%) of organic matter is contributed by C3 plants (freshwater algae) in the estuaries located in the northern (southern) India.

  6. Circulation and physical processes within the San Gabriel River Estuary during summer 2005

    USGS Publications Warehouse

    Rosenberger, Kurt J.; Xu, Jingping; Stein, Eric D.; Noble, Marlene A.; Gartner, Anne L.

    2007-01-01

    The Southern California Coastal Water Research Project (SCCWRP) is developing a hydrodynamic model of the SGR estuary, which is part of the comprehensive water-quality model of the SGR estuary and watershed investigated by SCCWRP and other local agencies. The hydrodynamic model will help understanding of 1) the exchange processes between the estuary and coastal ocean; 2) the circulation patterns in the estuary; 3) upstream natural runoff and the cooling discharge from PGS. Like all models, the SGR hydrodynamic model is only useful after it is fully calibrated and validated. In May 2005, SCCWRP requested the assistance of the U.S. geological Survey (USGS) Coastal and Marine Geology team (CMG) in collecting data on the hydrodynamic conditions in the estuary during the summer dry season. The summer was chosen for field data collection as this was assumed to be the season with the greatest potential for chronic degraded water quality due to low river flow and high thermal stratification within the estuary (due to both higher average air temperature and PGS output). Water quality can be degraded in winter as well, when higher river discharge events bring large volumes of water from the Los Angeles basin into the estuary. The objectives of this project were to 1) collect hydrodynamic data along the SGR estuary; 2) study exchange processes within the estuary through analysis of the hydrodynamic data; and 3) provide field data for model calibration and validation. As the data only exist for the summer season, the results herein only apply to summer conditions.

  7. 12 CFR 618.8025 - Feasibility reviews.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...618.8025 Feasibility reviews. ...recently completed business cycle (generally...performed a feasibility analysis pursuant to...recently completed business cycle (generally...performed a feasibility analysis pursuant...

  8. 24 CFR 241.1010 - Feasibility letter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Commissioner to undertake a feasibility analysis of an equity or acquisition...discretion of the Commissioner the feasibility analysis may be undertaken or denied...charge a fee for undertaking a feasibility analysis or for the issuance of...

  9. Multibiomarker assessment of three Brazilian estuaries using oysters as bioindicators

    SciTech Connect

    Valdez Domingos, F.X. [Departamento de Biologia Celular, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil)], E-mail: fa_valdez@yahoo.com; Azevedo, M. [Departamento de Fisiologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Silva, M.D. [Departamento de Farmacologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Randi, M.A.F. [Departamento de Biologia Celular, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Freire, C.A. [Departamento de Fisiologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Silva de Assis, H.C. [Departamento de Farmacologia, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil); Oliveira Ribeiro, C.A. [Departamento de Biologia Celular, Universidade Federal do Parana. CP. 19031, CEP 81531-990, Curitiba, PR (Brazil)

    2007-11-15

    Oysters have been largely employed as bioindicators of environmental quality in biomonitoring studies. Crassostrea rhizophorae was selected to evaluate the health status of three estuarine areas impacted by anthropogenic activities along the Brazilian coast, in three estuarine complexes, ranging in latitude from 7 to 25 deg. S. In each estuary three sites were sampled in Winter and in Summer: a site considered as reference, and two sites next to contamination sources. Condition index was similar at all sites and estuaries, with the highest values found for Itamaraca oysters in Summer. Necrosis, hyperplasia, mucocyte hypertrophy and fusion of ordinary filaments were the main histopathological lesions observed. Muscle cholinesterase activity was overall similar, but with a strong seasonal effect. Inhibition or activation of branchial total ATPase and Na,K-ATPase activities at the contaminated sites was observed. The health status of these estuarine areas is quite similar, and the combined use of biomarkers is recommended.

  10. Mercury bioaccumulation in organisms from three Puerto Rican estuaries.

    PubMed

    Burger, J; Cooper, K; Saliva, J; Gochfeld, D; Lipsky, D; Gochfeld, M

    1992-09-01

    We analyzed mercury levels in shrimp (Palaemonetes sp.), Blue Crabs (Callinectes sp.), fish (Tarpon Megalops atlantica and Tilapia Tilapia mossambica), lizards (Ameiva exsul), Cattle Egret (Bubulcus ibis) and Moorhen (Gallinula chloropus) in three estuaries in Puerto Rico in 1988. There were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site. Mercury levels were also below detection limits in Tilapia, except for specimens collected at Frontera Creek, allegedly contaminated with mercury. However, mercury levels ranged from 92-238 ?g/kg (wet weight) in Tarpon, a predaceous fish that feeds on smaller fish. Few of the birds had detectable levels of mercury. Our results indicate relatively low concentrations of mercury in biota collected in all of the three estuaries at most trophic levels, although 10 of 12 Tarpon fillet samples from Frontera had detectable mercury compared to 3 of 12 fillet samples for the other two lagoons. PMID:24226951

  11. Assessment of sediment contaminants and toxicity in the Delaware estuary

    SciTech Connect

    Costa, H.J. [Arthur D. Little, Inc., Cambridge, MA (United States); Sauer, T.C. [Battelle Ocean Sciences, Duxbury, MA (United States); Ward, T.J.; Boeri, R.L. [T.R. Wilbury Labs., Inc., Marblehead, MA (United States); Nyman, R.M. [Environmental Protection Agency, New York, NY (United States)

    1994-12-31

    In support of the Delaware Estuary Program`s Comprehensive Conservation and Management Plan, a study was performed to assess the spatial distribution of sediment toxicity in the Delaware Estuary and investigate potential causative contaminants. Twelve stations were sampled along the Delaware River covering 55 river miles between the Chesapeake and Delaware Canal and Torresdale, PA. Four additional stations were sampled in the mid-bay portion of Delaware Bay. Ten-day sediment static acute toxicity tests with amphipods (Ampelisca abdita) were performed for all stations. Sediments were analyzed for polynuclear aromatic hydrocarbons (PAHs), polychlorinated biphenyls, chlorinated pesticides, priority pollutant metals, and supporting parameters. Statistical analyses revealed positive correlations between sediment toxicity and PAH, lead, copper, and mercury concentrations. The highest incidences of sediment toxicity and highest concentrations of chemical contaminants occurred in the portion of the Delaware River between River Miles 60 and 75.

  12. Estimation of bed shear stresses in the pearl river estuary

    NASA Astrophysics Data System (ADS)

    Liu, Huan; Wu, Jia-xue

    2015-03-01

    Mean and fluctuating velocities were measured by use of a pulse coherent acoustic Doppler profiler (PC-ADP) and an acoustic Doppler velocimeter in the tidal bottom boundary layer of the Pearl River Estuary. The bed shear stresses were estimated by four different methods: log profile (LP), eddy correlation (EC), turbulent kinetic energy (TKE), and inertial dissipation (ID). The results show that (a) all four methods for estimating bed stresses have advantages and disadvantages, and they should be applied simultaneously to obtain reliable frictional velocity and to identify potential sources of errors; (b) the LP method was found to be the most suitable to estimate the bed stresses in non-stratified, quasi-steady, and homogeneous flows; and (c) in the estuary where the semi-diurnal tidal current is dominant, bed shear stresses exhibit a strong quarter-diurnal variation.

  13. Chlorofluorocarbons in the Hudson estuary during summer months

    SciTech Connect

    Clark, J.F.; Smethie, W.M. Jr.; Simpson, H.J. [Columbia Univ., Palisades, NY (United States)] [Columbia Univ., Palisades, NY (United States)

    1995-10-01

    Chlorofluorocarbon (CFC) concentrations in the Hudson estuary were found to be greater than the atmospheric solubility equilibrium concentration, demonstrating that the entire reach is contaminated with CFCs from local wastewater discharge. Samples have been collected along the axis of the lower Hudson estuary over a 5-month period to assess temporal and spatial variability of their wastewater sources. The highest CFC concentrations were found in water collected near Manhattan. In this region, CFC-11 (CCl{sub 3}F) and CFC-12 (CCl{sub 2}F{sub 2}) were 3 to 5 and 10 to 20 times saturation, respectively. There appears to be a continuous CFC source in the New York City area, although the magnitude of this source declined during summer months. Other large CFC source were found near Albany, and in Haverstraw Bay (60 km north of Manhattan). 29 refs., 6 figs., 3 tabs.

  14. Acidification of Lower St. Lawrence Estuary Bottom Waters

    Microsoft Academic Search

    Alfonso Mucci; Michel Starr; Denis Gilbert; Bjorn Sundby

    2011-01-01

    Accumulation of metabolic CO2 can acidify marine waters above and beyond the ongoing acidification of the ocean by anthropogenic CO2. The impact of respiration on carbonate chemistry and pH is most acute in hypoxic and anoxic basins, where metabolic CO2 accumulates to high concentrations. The bottom waters of the Lower St. Lawrence Estuary (LSLE), where persistently severe hypoxia has developed

  15. Fine-sediment Dynamics in the Mekong River Estuary, Vietnam

    Microsoft Academic Search

    Eric Wolanski; Nguyen Ngoc Huan; Le Trong Dao; Nguyen Huu Nhan; Nguyen Ngoc Thuy

    1996-01-01

    Field studies of fine-sediment transport were carried out in the Mekong River estuary, Vietnam, in the high-flow season of November 1993. In the freshwater region, erosion and deposition of suspended sediment occurred at tidal frequency with a strong down-river transport at a mean velocity of 1ms?1and mean suspended-solid concentration of about 250mgl?1. Also, the suspended sediment was mostly fine silt,

  16. Subtidal variability in water levels inside a subtropical estuary

    NASA Astrophysics Data System (ADS)

    Henrie, Krista; Valle-Levinson, Arnoldo

    2014-11-01

    Year-long time series of water level are analyzed at five locations along the St. Johns River Estuary, Florida, to investigate propagation of subtidal pulses. Hilbert-transformed Empirical Orthogonal Functions (HEOFs) are obtained after a dominant seasonal signal is extracted from the data. These functions provide information on spatial structure and propagation phase of subtidal water level pulses. The first HEOF mode explains 96% of the subtidal variability and features an unusual spatial structure: amplitude attenuation (averaging 1 mm/km) to 55 km upstream, slight amplification (0.16 mm/km) over the middle 70 km, and attenuation (2.3 mm/km) over the final 18 km of the estuary. The phase suggests a shift from progressive to quasi-standing wave behavior at 55 km from the estuary mouth. Additionally, local minima in the phase suggest two sources of subtidal forcing: the coastal ocean and the upstream end. An analytical model describing the evolution of long waves through a channel with frictional damping is fit to the amplitude of HEOF mode 1. Solutions are obtained as a function of two parameters: the nondimensional length of the basin, ?, and the nondimensional frictional depth, ?. Values of ? between 0.55 and 0.67 and ? between 1.45 and 1.7 provide the best fit with the HEOF results (1% error or less). These values indicate a highly frictional environment in which the average subtidal wavelength is 10 times the basin length. Subtidal pulses in this estuary, therefore, behave as damped waves that can be represented with idealized models.

  17. Carbon biogeochemistry of the Betsiboka estuary (north-western Madagascar)

    Microsoft Academic Search

    Olivier Harifidy Ralison; Alberto Vieira Borges; Frank Dehairs; J. J. Middelburg; Steven Bouillon

    2008-01-01

    Madagascar’s largest estuary (Betsiboka) was sampled along the salinity gradient during the dry season to document the distribution and sources of particulate and dissolved organic carbon (POC, DOC) as well as dissolved inorganic carbon (DIC). The Betsiboka was characterized by a relatively high suspended matter load, and in line with this, low DOC\\/POC ratios (?0.4–2.5). The partial pressure of CO2

  18. Digital flow model of the Chowan River estuary, North Carolina

    USGS Publications Warehouse

    Daniel, C.C.

    1977-01-01

    A one-dimensional deterministic flow model based on the continuity equation had been developed to provide estimates of daily flow past a number of points on the Chowan River estuary of northeast North Carolina. The digital model, programmed in Fortran IV, computes daily average discharge for nine sites; four of these represent inflow at the mouths of major tributaries, the five other sites are at stage stations along the estuary. Because flows within the Chowan River and the lower reaches of its tributaries are tidally affected, flows occur in both upstream and downstream directions. The period of record generated by the model extends from April 1, 1974, to March 31, 1976. During the two years of model operation the average discharge at Edenhouse near the mouth of the estuary was 5,830 cfs (cubic feet per second). Daily average flows during this period ranged from 55,900 cfs in the downstream direction on July 17, 1975, to 14,200 cfs in the upstream direction on November 30, 1974

  19. Production by microphytobenthos in the Swan-Canning Estuary

    NASA Astrophysics Data System (ADS)

    Masini, R. J.; McComb, Arthur J.

    2001-09-01

    Intact sediment cores containing microphytobenthos, dominated by episammic diatoms, were collected from shallow sand flats of the Swan-Canning Estuary, Perth, southwestern Australia, and their photosynthesis-light relations deduced from changes in oxygen (17 cores) or pH (13 cores). The theoretical saturating light intensity Ik determined from O2 was 107 µE m-2 s-1, and the light intensity at which photosynthesis is saturated, Isat, was about 1100 µE m-2 s-1. Mean gross production and respiration increased with temperature. Infaunal contributions to total respiration were measured for two cores at about 30%.The sediment photic zone was estimated as 0·5 mm in fine sediments of the upper estuary and 3·5 mm in coarse sediments of the lower estuary. Microalgae from below the photic zone photosynthesized on exposure to light. Biomass (measured as chlorophyll a) decreased down the sediment profile and was linearly correlated with net and gross maximum photosynthesis. Relative photosynthetic efficiencies were high, and light compensation increased with increasing depth in the sediment.Q

  20. Dissolved oxygen conditions in northern Gulf of Mexico estuaries

    USGS Publications Warehouse

    Engle, V.D.; Kevin, Summers J.; Macauley, J.M.

    1999-01-01

    Because deficient dissolved oxygen (DO) levels may have severe detrimental effects on estuarine and marine life, DO has been widely used as an indicator of ecological conditions by environmental monitoring programs. The U.S. EPA's Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) monitored DO conditions in the estuaries of the Gulf of Mexico from 1991 to 1994. DO was measured in two ways: 1)instantaneous profiles from the surface to the bottom were taken during the day, and 2) continuous measurements were taken near the bottom at 15 min intervals for at least 12 h. This information was summarized to assess the spatial distribution and severity of DO conditions in these estuaries. Depending on the criteria used to define hypoxia (DO concentrations usually < 2 mg L-1 or 15 mg L-1) and the method by which DO is measured, we estimate that between 5.2 and 29.3% of the total estuarine area in the Louisianian Province was affected by low DO conditions.

  1. Counting on ?-diversity to safeguard the resilience of estuaries.

    PubMed

    de Juan, Silvia; Thrush, Simon F; Hewitt, Judi E

    2013-01-01

    Coastal ecosystems are often stressed by non-point source and cumulative effects that can lead to local-scale community homogenisation and a concomitant loss of large-scale ecological connectivity. Here we investigate the use of ?-diversity as a measure of both community heterogeneity and ecological connectivity. To understand the consequences of different environmental scenarios on heterogeneity and connectivity, it is necessary to understand the scale at which different environmental factors affect ?-diversity. We sampled macrofauna from intertidal sites in nine estuaries from New Zealand's North Island that represented different degrees of stress derived from land-use. We used multiple regression models to identify relationships between ?-diversity and local sediment variables, factors related to the estuarine and catchment hydrodynamics and morphology and land-based stressors. At local scales, we found higher ?-diversity at sites with a relatively high total richness. At larger scales, ?-diversity was positively related to ?-diversity, suggesting that a large regional species pool was linked with large-scale heterogeneity in these systems. Local environmental heterogeneity influenced ?-diversity at both local and regional scales, although variables at the estuarine and catchment scales were both needed to explain large scale connectivity. The estuaries expected a priori to be the most stressed exhibited higher variance in community dissimilarity between sites and connectivity to the estuary species pool. This suggests that connectivity and heterogeneity metrics could be used to generate early warning signals of cumulative stress. PMID:23755252

  2. Intertidal macrofaunal communities in an intensely polluted estuary.

    PubMed

    Bustamante, M; Tajadura-Martín, F J; Saiz-Salinas, J I

    2007-11-01

    The Bilbao estuary (northern Spain) has suffered a serious environmental deterioration due to industrial and domestic discharges during decades. A total of 21 sampling stations were selected in order to: (1) study the intertidal fauna distribution on both hard and soft bottoms; (2) link this information with the prevalence of certain environmental variables at the sampling sites; and (3) define distinct biological zones with all the information gathered. Up to 50 taxa were identified mainly in the outer estuary with an abrupt decrease upstream. In general, fauna on hard substrates was more diverse, while soft bottom communities exhibited a more consistent structure. Sporadic hypoxic events were recorded in the water column of all the sites studied, which affects the distribution of species. Three major biotic zones are proposed in the estuary. This provides a reliable biomonitoring tool for assessing the effectiveness of a sewerage and remediation scheme ongoing on the river and evaluating the future use of each area in the urban development of the city of Bilbao and conurbation. PMID:17370137

  3. Future variability of solute transport in a macrotidal estuary

    NASA Astrophysics Data System (ADS)

    Robins, Peter E.; Lewis, Matt J.; Simpson, John H.; Howlett, Eleanor R.; Malham, Shelagh K.

    2014-12-01

    The physical controls on salt distribution and river-sourced conservative solutes, including the potential implications of climate change, are investigated referring to model simulations of a macrotidal estuary. In the UK, such estuaries typically react rapidly to rainfall events and, as such, are often in a state of non-equilibrium in terms of solute transport; hence are particularly sensitive to climate extremes. Sea levels are projected to rise over the 21st century, extending the salinity maximum upstream in estuaries, which will also affect downstream solute transport, promoting estuarine trapping and reducing offshore dispersal of material. Predicted 'drier summers' and 'wetter winters' in the UK will influence solute transport further still; we found that projected river flow climate changes were more influential than sea-level rise, especially for low flow conditions. Our simulations show that projected climate change for the UK is likely to increase variability in estuarine solute transport and, specifically, increase the likelihood of estuarine trapping during summer, mainly due to drier weather conditions. Future changes in solute transport were less certain during winter, since increased river flow will to some extent counter-act the effects of sea-level rise. Our results have important implications for non-conservative nutrient transport, water quality, coastal management and ecosystem resilience.

  4. Counting on ?-Diversity to Safeguard the Resilience of Estuaries

    PubMed Central

    de Juan, Silvia; Thrush, Simon F.; Hewitt, Judi E.

    2013-01-01

    Coastal ecosystems are often stressed by non-point source and cumulative effects that can lead to local-scale community homogenisation and a concomitant loss of large-scale ecological connectivity. Here we investigate the use of ?-diversity as a measure of both community heterogeneity and ecological connectivity. To understand the consequences of different environmental scenarios on heterogeneity and connectivity, it is necessary to understand the scale at which different environmental factors affect ?-diversity. We sampled macrofauna from intertidal sites in nine estuaries from New Zealand’s North Island that represented different degrees of stress derived from land-use. We used multiple regression models to identify relationships between ?-diversity and local sediment variables, factors related to the estuarine and catchment hydrodynamics and morphology and land-based stressors. At local scales, we found higher ?-diversity at sites with a relatively high total richness. At larger scales, ?-diversity was positively related to ?-diversity, suggesting that a large regional species pool was linked with large-scale heterogeneity in these systems. Local environmental heterogeneity influenced ?-diversity at both local and regional scales, although variables at the estuarine and catchment scales were both needed to explain large scale connectivity. The estuaries expected a priori to be the most stressed exhibited higher variance in community dissimilarity between sites and connectivity to the estuary species pool. This suggests that connectivity and heterogeneity metrics could be used to generate early warning signals of cumulative stress. PMID:23755252

  5. Carbon dioxide emissions from estuaries of northern and northeastern Brazil

    NASA Astrophysics Data System (ADS)

    Noriega, Carlos; Araujo, Moacyr

    2014-08-01

    The carbon dioxide flux through the air-water interface of coastal estuarine systems must be quantified to understand the regional balance of carbon and its transport through adjacent coastal regions. We estimated and calculated the emissions of carbon dioxide (FCO2) and the partial pressure of CO2 (pCO2) values in 28 estuarine environments at a variety of spatial scales in the northern and northeastern regions of Brazil. The results showed a mean FCO2 (water to air) of 55 +/- 45 mmol.m-2.d-1. Additionally, a negative correlation between dissolved oxygen saturation and pCO2 was observed, indicating a control by biological processes and especially by organic matter degradation. This leads to increased dissolved CO2 concentration in estuarine waters which results in a pCO2 that reached 8,638 ?atm. Our study suggests that northern and northeastern Brazilian estuaries act as sources of atmospheric CO2. The range of pCO2 observed were similar to those found in inner estuaries in other places around the world, with the exception of a few semi-arid estuaries (Köppen climate classification - BSh) in which record low levels of pCO2 have been detected.

  6. Predicting habitat associations of five intertidal crab species among estuaries

    NASA Astrophysics Data System (ADS)

    Vermeiren, Peter; Sheaves, Marcus

    2014-08-01

    Intertidal crab assemblages that are active on the sediment surface of tropical estuaries during tidal exposure play an important role in many fundamental ecosystem processes. Consequently, they are critical contributors to a wide range of estuarine goods and services. However, a lack of understanding of their spatial organization within a large landscape context prevents the inclusion of intertidal crabs into generally applicable ecological models and management applications. We investigated spatial distribution patterns of intertidal crabs within and among eight dry tropical estuaries spread across a 160 km stretch of coast in North East Queensland, Australia. Habitat associations were modelled for five species based on photographic sampling in 40-80 sites per estuarine up- and downstream component: Uca seismella occurred in sites with little structure, bordered by low intertidal vegetation; Macrophthalmus japonicus occupied flat muddy sites with no structure or vegetation; Metopograpsus frontalis and Metopograpsus latifrons occupied sites covered with structure in more than 10% and 25% respectively. Finally, both Metopograpsus spp. and Metopograpsus thukuhar occupied rock walls. Habitat associations were predictable among estuaries with moderate to high sensitivity and low percentages of false positives indicating that simple, physical factors were adequate to explain the spatial distribution pattern of intertidal crabs. Results provide a necessary first step in developing generally applicable understanding of the fundamental mechanisms driving spatial niche organization of intertidal crabs within a landscape context.

  7. Feasibility analysis of recycling radioactive scrap steel

    SciTech Connect

    Nichols, F. [Manufacturing Sciences Corp., Woodland, WA (United States); Balhiser, B. [MSE, Inc., Butte, MT (United States); Cignetti, N. [Cignetti Associates, North Canton, OH (United States)] [and others

    1995-09-01

    The purpose of this study is to: (1) establish a conceptual design that integrates commercial steel mill technology with radioactive scrap metal (RSM) processing to produce carbon and stainless steel sheet and plate at a grade suitable for fabricating into radioactive waste containers; (2) determine the economic feasibility of building a micro-mill in the Western US to process 30,000 tons of RSM per year from both DOE and the nuclear utilities; and (3) provide recommendations for implementation. For purposes of defining the project, it is divided into phases: economic feasibility and conceptual design; preliminary design; detail design; construction; and operation. This study comprises the bulk of Phase 1. It is divided into four sections. Section 1 provides the reader with a complete overview extracting pertinent data, recommendations and conclusions from the remainder of the report. Section 2 defines the variables that impact the design requirements. These data form the baseline to create a preliminary conceptual design that is technically sound, economically viable, and capitalizes on economies of scale. Priorities governing the design activities are: (1) minimizing worker exposure to radionuclide hazards, (2) maximizing worker safety, (3) minimizing environmental contamination, (4) minimizing secondary wastes, and (5) establishing engineering controls to insure that the plant will be granted a license in the state selected for operation. Section 3 provides details of the preliminary conceptual design that was selected. The cost of project construction is estimated and the personnel needed to support the steel-making operation and radiological and environmental control are identified. Section 4 identifies the operational costs and supports the economic feasibility analysis. A detailed discussion of the resulting conclusions and recommendations is included in this section.

  8. RELATIONS OF FISH AND SHELLFISH DISTRIBUTIONS TO HABITAT AND WATER QUALITY IN THE MOBILE BAY ESTUARY, USA

    EPA Science Inventory

    The Mobile Bay estuary provides rich habitat for many fish and shellfish, including those identified as economically and ecologically important. The National Estuary Program has focused on restoration of degraded estuarine habitat on which these species depend. To support this ...

  9. Variation in tidal wetland plant diversity and composition within and among coastal estuaries: assessing the relative importance of environmental gradients

    EPA Science Inventory

    Question: Does wetland plant composition vary more by estuarine type (differentiated by the degree of riverine versus oceanic influence) or habitat type within estuaries (defined by US National Wetlands Inventory [NWI] marsh classes)? Location: Oregon estuaries: Netarts Bay, Yaq...

  10. Estuaries of the northeastern United States: Habitat and land use signatures

    USGS Publications Warehouse

    Roman, C.T.; Jaworski, N.; Short, F.T.; Findlay, S.; Warren, R.S.

    2000-01-01

    Geographic signatures are physical, chemical, biotic, and human-induced characteristics or processes that help define similar or unique features of estuaries along latitudinal or geographic gradients. Geomorphologically, estuaries of the northeastern U.S., from the Hudson River estuary and northward along the Gulf of Maine shoreline, are highly diverse because of a complex bedrock geology and glacial history. Back-barrier estuaries and lagoons occur within the northeast region, but the dominant type is the drowned-river valley, often with rocky shores. Tidal range and mean depth of northeast estuaries are generally greater when compared to estuaries of the more southern U.S. Atlantic coast and Gulf of Mexico. Because of small estuarine drainage basins, low riverine flows, a bedrock substrate, and dense forest cover, sediment loads in northeast estuaries are generally quite low and water clarity is high. Tidal marshes, seagrass meadows, intertidal mudflats, and rocky shores represent major habitat types that fringe northeast estuaries, supporting commercially-important fauna, forage nekton and benthos, and coastal bird communities, while also serving as links between deeper estuarine waters and habitats through detritus-based pathways. Regarding land use and water quality trends, portions of the northeast have a history of over a century of intense urbanization as reflected in increased total nitrogen and total phosphorus loadings to estuaries, with wastewater treatment facilities and atmospheric deposition being major sources. Agricultural inputs are relatively minor throughout the northeast, with relative importance increasing for coastal plain estuaries. Identifying geographic signatures provides an objective means for comparing the structure function, and processes of estuaries along latitudinal gradients.

  11. Dissolved inorganic nutrients and chlorophyll A in an estuary receiving sewage treatment plant effluents: Cachoeira River estuary (NE Brazil).

    PubMed

    Silva, Maria Aparecida Macêdo; Eça, Gilmara Fernandes; Santos, Danielle Felix; Guimarães, Alonso Góes; Lima, Michelle Coêlho; de Souza, Marcelo Friederichs Landim

    2013-07-01

    Sampling was conducted monthly during a transition period between the dry and rainy seasons in order to evaluate the effectiveness of a municipal sewage treatment plant (STP) in eutrophication control. STP effluent and fluvial input data were also estimated. In the dry period, high concentrations of nutrients, chlorophyll a (up to 360 ?g?L(-1)), and anoxia in bottom waters were observed in the upper portion of the estuary. Nitrate was scarce during the dry months, although high concentrations were observed at the river sources and the upper estuary. The N:P and Si:P molar ratios were usually below 16:1, and the Si:N ratio was higher than 1:1. The fluvial inputs were a greater source of nutrients to the estuary than the STP, but nutrient loading by these effluents were also important in contributing to the eutrophication of the upper estuarine zone, especially in the dry season when symptoms were more intense. PMID:23179722

  12. Silver behaviour along the salinity gradient of the Gironde Estuary.

    PubMed

    Lanceleur, Laurent; Schäfer, Jörg; Blanc, Gérard; Coynel, Alexandra; Bossy, Cécile; Baudrimont, Magalie; Glé, Corine; Larrose, Aurélie; Renault, Sophie; Strady, Emilie

    2013-03-01

    Dissolved and particulate Ag concentrations (Ag(D) and Ag(P), respectively) were measured in surface water and suspended particulate matter (SPM) along the salinity gradient of the Gironde Estuary, South West France, during three cruises (2008-2009) covering contrasting hydrological conditions, i.e. two cruises during intermediate and one during high freshwater discharge (~740 and ~2,300 m(3)/s). Silver distribution reflected non-conservative behaviour with 60-70 % of Ag(P) in freshwater particles being desorbed by chlorocomplexation. The amount of Ag(P) desorbed was similar to the so-called reactive, potentially bioavailable Ag(P) fraction (60 ± 4 %) extracted from river SPM by 1 M HCl. Both Ag(P) (0.22 ± 0.05 mg/kg) and Ag(P)/Th(P) (0.025-0.028) in the residual fraction of fluvial and estuarine SPM were similar to those in SPM from the estuary mouth and in coastal sediments from the shelf off the Gironde Estuary, indicating that chlorocomplexation desorbs the reactive Ag(P). The data show that desorption of reactive Ag(P) mainly occurs inside the estuary during low and intermediate discharge, whereas expulsion of partially Ag(P)-depleted SPM (Ag(P)/Th(P) ~0.040) during the flood implies ongoing desorption in the coastal ocean, e.g. in the nearby oyster production areas (Marennes-Oléron Bay). The highest Ag(D) levels (6-8 ng/L) occurred in the mid-salinity range (15-20) of the Gironde Estuary and were decoupled from freshwater discharge. In the maximum turbidity zone, Ag(D) were at minimum, showing that high SPM concentrations (a) induce Ag(D) adsorption in estuarine freshwater and (b) counterbalance Ag(P) desorption in the low salinity range (1-3). Accordingly, Ag behaviour in turbid estuaries appears to be controlled by the balance between salinity and SPM levels. The first estimates of daily Ag(D) net fluxes for the Gironde Estuary (Boyle's method) showed relatively stable theoretical Ag(D) at zero salinity (Ag (D) (0) = 25-30 ng/L) for the contrasting hydrological situations. Accordingly, Ag(D) net fluxes were very similar for the situations with intermediate discharge (1.7 and 1.6 g/day) and clearly higher during the flood (5.0 g/day) despite incomplete desorption. Applying Ag (D) (0) to the annual freshwater inputs provided an annual net Ag(D) flux (0.64-0.89 t/year in 2008 and 0.56-0.77 t/year in 2009) that was 12-50 times greater than the Ag(D) gross flux. This estimate was consistent with net Ag(D) flux estimates obtained from gross Ag(P) flux considering 60 % desorption in the estuarine salinity gradient. PMID:22782792

  13. Engineering Electrical &

    E-print Network

    Hickman, Mark

    Computer Engineering Electrical & Electronic Engineering Mechatronics Engineering Mechanical Engineering Civil Engineering Natural Resources Engineering Forest Engineering Chemical & Process Engineering ELECTIVE 2 Required Engineering Intermediate Year 2012 Eight Required Courses Chart: 120 points College

  14. Engineering Electrical &

    E-print Network

    Hickman, Mark

    Computer Engineering Electrical & Electronic Engineering Mechatronics Engineering Mechanical Engineering Civil Engineering Natural Resources Engineering Forest Engineering Chemical & Process Engineering ELECTIVE 2 Required Engineering Intermediate Year 2011 Eight Required Courses Chart: 120 points College

  15. ECOLOGICAL CONDITION OF THE U.S. MID-ATLANTIC ESTUARIES: THE MID-ATLANTIC INTEGRATED ASSESSMENT (MAIA)

    EPA Science Inventory

    The Mid-Atlantic Integrated Assessment (MAIA-Estuaries) evaluated ecological conditions in US Mid-Atlantic estuaries during the summers of 1997 and 1998. Over 800 probability-based stations were monitored in four main estuarine systems?Chesapeake Bay, the Delaware Estuary, Maryla...

  16. A model study of the circulation in the Pearl River Estuary (PRE) and its adjacent coastal waters

    E-print Network

    Maine, University of

    A model study of the circulation in the Pearl River Estuary (PRE) and its adjacent coastal waters results with the in situ measurements collected during the Pearl River Estuary Pollution Project (PREPP. Xue, L. X. Dong, W. B. Guan, and J. L. Su, A model study of the circulation in the Pearl River Estuary

  17. Ecological Aspects of the Annapolis Estuary With Specific Reference to Operational Effects of the Annapolis Tidal Power Station

    Microsoft Academic Search

    Anna M. Redden; Graham R. Daborn; Robert S. Gregory

    Results of physico-chemical and biological studies in the Annapolis Estuary are reviewed with reference to possible environmental effects of the Annapolis Tidal Power Station. Tidal barrage construction in 1960 transformed a vertically homogenous type of estuary into a highly stratf- fled salt wedge estuary with a reduced tidal range. Stratification is highly stable in the lower river and variable in

  18. Behaviour of Turbidity Maxima in the Tamar (U.K.) and Weser (F.R.G.) Estuaries

    Microsoft Academic Search

    I. Grabemann; R. J. Uncles; G. Krause; J. A. Stephens

    1997-01-01

    The Tamar (England) and Weser (Germany) Estuaries exhibit strong turbidity maxima in their low-salinity reaches. Whereas their morphologies and freshwater inflows are different, the estuaries have similar mean tidal ranges and mean tidal current speeds. Despite the differences, the turbidity maxima show similar intratidal, spring–neap and seasonal behaviour for the two estuaries. On an intratidal time scale, strong suspended particulate

  19. E-Estuary: Developing a Decision Support System for Coastal Management in the Conterminous United States (IAHR)

    EPA Science Inventory

    Ready access to geographic information is needed to support management decisions for estuaries at local, state, regional, and national scales. The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary ...

  20. E-Estuary: Developing a Decision-support System for Coastal Management in the Counterminous Untied States (Coastal Geotools 09)

    EPA Science Inventory

    Ready access to geographic information is needed to support management decisions for estuaries at local, state, regional, and national scales. The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary ...

  1. E-estuary: A Decision Support System for Coastal Water and Ecosystem Management in the US (CZ09)

    EPA Science Inventory

    Ready access to geographic information is needed to support management decisions for estuaries at local, state, regional, and national scales. The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary ...

  2. Lower Sioux Wind Feasibility & Development

    SciTech Connect

    Minkel, Darin

    2012-04-01

    This report describes the process and findings of a Wind Energy Feasibility Study (Study) conducted by the Lower Sioux Indian Community (Community). The Community is evaluating the development of a wind energy project located on tribal land. The project scope was to analyze the critical issues in determining advantages and disadvantages of wind development within the Community. This analysis addresses both of the Community's wind energy development objectives: the single turbine project and the Commerical-scale multiple turbine project. The main tasks of the feasibility study are: land use and contraint analysis; wind resource evaluation; utility interconnection analysis; and project structure and economics.

  3. Conceptualizing the Structure of Coupled Estuary, Coast and Inner Shelf Sediment Systems

    NASA Astrophysics Data System (ADS)

    French, J.; Burningham, H.

    2013-12-01

    The concept of the coastal cell has endured for 50 years as a geomorphological framework for coastal engineering and management. Cells are readily defined for coasts dominated by alongshore transport of beach-grade material, but the concept struggles to accommodate long range cohesive sediment fluxes. Moreover, the challenges of predicting, understanding and mitigating climate change impacts at the coast demand a richer conceptualization that embraces the connectedness of open coasts with estuaries and the inner shelf at broader scales and that also acknowledges the extent of anthropogenic control. Accordingly, this paper presents a new approach that re-engages with formal systems analysis and restores a geomorphological focus to coastal management problems that have latterly been tackled primarily by engineers. At the heart of this approach is an ontology of landforms and interventions (both structural and non-structural) that is partly inspired by the coastal tract concept and its temporal hierarchy of sediment sharing systems, but which also emphasizes a spatial hierarchy in scale, from coastal regions, through landform complexes, to landforms and human interventions. The complex web of interactions is represented through an influence network in which a sub-set of mass transfer pathways define the sediment system. Guided by a machine-readable ontology and produced within a geospatial framework, such system ';maps' can be utilized in several ways. First, their generation constitutes a form of knowledge formalization in which disparate sources of information (published research, data etc) are generalized into usable knowledge. Second, system maps also provide a repository for more quantitative analyses and system-level modelling at the scales that really matter. Third, they can also be analyzed using methods derived from graph theory to yield potentially valuable insights into the scale linkages that govern the mutual adjustment of estuary, coast and inner shelf morphology and their implications for the development of quantitative models able to capture such behaviour. Illustrative results, produced as a contribution to the NERC Integrated Coastal Sediment Systems (iCOASST) project, are presented for demonstration regions in Liverpool Bay and Suffolk, UK.

  4. RELATIONSHIPS BETWEEN SEAGRASSES, BENTHIC MACROALGAE AND NUTRIENTS IN A PACIFIC NORTHWEST ESTUARY

    EPA Science Inventory

    Pacific Northwest estuaries are characterized by large tidal ranges (2-3 m) that routinely expose submerged aquatic vegetation (SAV) such as seagrass and benthic macroalgae. The dominant native seagrass in PNW estuaries is the eelgrass Zostera marina. However, in recent decades...

  5. Transport of fallout and reactor radionuclides in the drainage basin of the Hudson River estuary

    SciTech Connect

    Simpson, H.J.; Linsalata, P.; Olsen, C.R.

    1982-01-01

    The transport and fate of Strontium 90, Cesium 137 and Plutonium 239, 240 in the Hudson River Estuary is discussed. Rates of radionuclide deposition and accumulation over time and space are calculated for the Hudson River watershed, estuary, and continental shelf offshore. 37 references, 7 figures, 15 tables. (ACR)

  6. Long-term morphological change and its causes in the Mersey Estuary, NW England

    Microsoft Academic Search

    Simon J. Blott; Kenneth Pye; Daphne van der Wal; Adrian Neal

    2006-01-01

    Changes in the morphology of the Mersey Estuary, and their possible causes, have been investigated using Historical Trend Analysis and Expert Geomorphological Assessment. Historical bathymetric charts were digitised and analysed within a GIS to provide quantitative estimates of changes in areas and sediment volumes above and below selected elevation planes. The results show that the estuary experienced major changes over

  7. Natural and anthropogenic hydrocarbon inputs to sediments of Patos Lagoon Estuary, Brazil

    Microsoft Academic Search

    Patricia Matheus Medeiros; Márcia Caruso Bícego; Renato Menezes Castelao; Clarissa Del Rosso; Gilberto Fillmann; Ademilson Josemar Zamboni

    2005-01-01

    The Patos Lagoon Estuary, southern Brazil, is an area of environmental interest not only because of tourism, but also because of the presence of the second major port of Brazil, with the related industrial and shipping activities. Thus, potential hydrocarbon pollution was examined in this study. Sediment samples were collected at 10 sites in the estuary, extracted, and analyzed by

  8. Rapid coastal geomorphic change in the River Murray Estuary of Australia

    Microsoft Academic Search

    R. P. Bourman; C. V. Murray-Wallace; A. P. Belperio; N. Harvey

    2000-01-01

    The River Murray Estuary, a Ramsar Wetland Site, has experienced considerable rapid coastal change during the Quaternary. The interplay of aeolian processes, river flows, tidal oscillations, wave action and variations in relative sea-level due to global sea-level changes and land subsidence, provides the energy for the ongoing dynamism, often accelerated by human impacts. The estuary is the terminus of the

  9. Total and inorganic arsenic in the fauna of the Guadalquivir estuary: environmental and human health implications

    Microsoft Academic Search

    M. A Suñer; V Devesa; O Muñoz; F López; R Montoro; A. M Arias; J Blasco

    1999-01-01

    To evaluate the impact on fauna of the release of toxic waste from the tailings dam operated by the Boliden Apirsa S.L company at Aznalcóllar, Seville (Spain) a study was carried out of total and inorganic arsenic contents in 164 samples from six different estuary species, including molluscs, crustaceans and fish, collected at six sampling stations distributed along the estuary

  10. Nutrient Behaviour During Post-flood Recovery of the Richmond River Estuary, Northern NSW, Australia

    Microsoft Academic Search

    Bradley D Eyre; Colleen Twigg

    1997-01-01

    Dissolved and particulate inorganic and organic forms of phosphorus and nitrogen, suspended sediments, dissolved silica and physico-chemical parameters were examined in the Richmond River Estuary following a small flood event. Under flood conditions, nutrient concentrations were elevated, estuarine processes were bypassed and freshwater, sediments and nutrients were discharged directly onto the continental shelf. The Estuary recovered by way of a

  11. 33 CFR 165.1190 - Security Zone; San Francisco Bay, Oakland Estuary, Alameda, CA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Security Zone; San Francisco Bay, Oakland Estuary, Alameda...District § 165.1190 Security Zone; San Francisco Bay, Oakland Estuary, Alameda...by the Coast Guard Captain of the Port, San Francisco Bay, or his designated...

  12. Absorption and fluorescence of chromophoric dissolved organic matter in the Pearl River Estuary, South China

    E-print Network

    Absorption and fluorescence of chromophoric dissolved organic matter in the Pearl River Estuary Available online 15 August 2005 Abstract The Pearl River is a complex river network under the influence of heavy urbanization and industrialization. The Pearl River Estuary receives freshwater from eight major

  13. Concentration and Distribution of Hydrophobic Organic Contaminants and Metals in the Estuaries of Ukraine

    EPA Science Inventory

    In this baseline study of Ukrainian estuaries, sediments and organisms from the Dnieper and Boh estuaries and Danube Delta on the mainland, Sevastopol and Balaklava Bays on the Crimean Peninsula, and coastal Black Sea along the Crimean Peninsula were collected in 2006. Contamina...

  14. NAME: Salt Creek Estuary Restoration LOCATION: Salt Creek Watershed, Clallam County, Washington

    E-print Network

    US Army Corps of Engineers

    NAME: Salt Creek Estuary Restoration LOCATION: Salt Creek Watershed, Clallam County, Washington Federal funds $0 PROJECT DESCRIPTION: The Salt Creek Estuary Reconnection project will significantly enhance tidal and fluvial hydrology to 22.5 acres of salt marsh, which will return the salt marsh to its

  15. Distribution, transport and exchanges of fine sediment, with tidal power implications: Severn Estuary, UK

    Microsoft Academic Search

    R. Kirby

    2010-01-01

    The Severn, a hypertidal, high turbidity estuary, has a bed largely stripped of unconsolidated sediment. Its inter-tidal zone is mainly mudflats, the universal erosional trend of which is now proven. These are a source for sub-tidal mud accumulations in Newport Deep, much of Bridgwater Bay, less so in Bristol Deep and Cardiff Roads. The main estuary turbidity maximum is dominated

  16. A MODEL OF ESTUARY RESPONSE TO NITROGEN LOADING AND FRESHWATER RESIDENCE TIME

    EPA Science Inventory

    We have developed a deterministic model that relates average annual nitrogen loading rate and water residence time in an estuary to in-estuary nitrogen concentrations and loss rates (e.g. denitrification and incorporation in sediments), and to rates of nitrogen export across the ...

  17. The Larval Fish Assemblage in Nearshore Coastal Waters off the St Lucia Estuary, South Africa

    Microsoft Academic Search

    S. A Harris; D. P Cyrus; L. E Beckley

    1999-01-01

    This paper reports on the composition, abundance and distribution of the larval fish assemblage in the nearshore coastal waters off the St Lucia Estuary mouth, South Africa. Ichthyoplankton samples were collected over a 12 month period from five stations located along a transect up to 2·5km offshore, and from two stations north and south of the estuary mouth, respectively. In

  18. Developing Nitrogen Load-Eelgrass Response Relationshups for New England Estuaries

    EPA Science Inventory

    We have accumulated and analyzed eelgrass areal extent data for 67 estuaries from three New England states. To our knowledge this is the largest data set of its kind. Previous comparative studies have utilized data from a far smaller number of estuaries (ten or less) to develop e...

  19. The Distribution of Salinity and Temperature in the Connecticut River Estuary

    Microsoft Academic Search

    Richard W. Garvine

    1975-01-01

    Measurements of near-surface salinity and temperature were made over a period of 16 months in the Connecticut River estuary, an estuary basically of the salt wedge type. Theemperature distribution was found to be Very highly correlated with the salinity distribution. The horizontal salinity distribution oc- curred primarily in two modes, a riverinc mode and a plume mode, corresponding to salinity

  20. Linking Data Access to Data Models to Applications: The Estuary Data Mapper

    EPA Science Inventory

    The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for coastal management. E-Estuary has three elements: an estuarine geo-referenced relational database, watershed GIS coverages, and tools to support decision-making. To facilita...

  1. Valuing Estuarine Resource Services Using Economic and Ecological Models: The Peconic Estuary System Study

    Microsoft Academic Search

    Robert J. Johnston; Thomas A. Grigalunas; James J. Opaluch; Marisa Mazzotta; Jerry Diamantedes

    2002-01-01

    This article summarizes four integrated economic studies undertaken to contribute to resource preservation and restoration decisions for the Peconic Estuary System of Suffolk County, NY. Completed as part of the National Estuary Program, the studies apply distinct resource valuation methods to a wide range of resource issues. The principal goals of this article are to highlight different methodologies that may

  2. EFFECTS OF EROSION AND MACROALGAE ON INTERTIDAL EELGRASS (ZOSTERA MARINA) IN A NORTHEASTERN PACIFIC ESTUARY (USA)

    EPA Science Inventory

    Eelgrass (Zostera marina) in open-coast northeastern Pacific estuaries is primarily intertidal, yet little research has been done on the natural factors controlling its upper intertidal growth limits. This two-year study in the Yaquina Estuary (Newport, Oregon, USA) evaluated the...

  3. REGIONAL TRANSPORT AND SECONDARY SPREAD OF INVASIVE SPECIES ACROSS PACIFIC ESTUARIES

    EPA Science Inventory

    San Francisco Bay is considered to be the most highly invaded estuary in North America, and is suspected of acting as a local source pool for secondary invasions of other Pacific estuaries. With support from the Regional Applied Research Effort programs in EPA Regions 9 and 10, ...

  4. San Francisco Estuary Regional Monitoring Program for Trace Substances Estimates of Suspended-sediment Flux

    E-print Network

    San Francisco Estuary Regional Monitoring Program for Trace Substances Estimates of Suspended (SPLWG) San Francisco Estuary Regional Monitoring Program for Trace Substances (RMP) December 2002 #12;Mc for the Sources Pathways and Loading Workgroup (SPLWG) of the San Francisco Bay Regional Monitoring Program

  5. San Francisco Estuary Regional Monitoring Program for Trace Substances Concentrations and Loads of Organic

    E-print Network

    San Francisco Estuary Regional Monitoring Program for Trace Substances Concentrations and Loads, California June 2005 RMP Technical Report San Francisco Estuary Regional Monitoring Program for Trace) of the Regional Monitoring Program for Trace Substances (RMP) for participation and guidance in all stages

  6. STABLE ISOTOPE VARIATIONS IN SUSPENDED PARTICLES IN A TEMPERATE NORTH PACIFIC ESTUARY, OREGON, USA

    EPA Science Inventory

    Spatial distributions of 13C and 15N in suspended particles were examined monthly over an annual cycle in the euphotic zone (0.5m) of the Yaquina River and Estuary, Oregon. Suspended organic matter in estuaries is a mixture of land-derived and oceanic carbon and nitrogen. In a...

  7. Environmental Research 105 (2007) 5366 Decadal mercury trends in San Francisco Estuary sediments

    E-print Network

    The history of mercury contamination and regulation in San Francisco Estuary spans more than 150 years (Table small, and attributed the bulk of the mercury contamination in the area to historic gold and mercuryEnvironmental Research 105 (2007) 53­66 Decadal mercury trends in San Francisco Estuary sediments

  8. Padal fishing - a unique fishing method in the Ashtamudi Estuary of Kerala (south India)

    Microsoft Academic Search

    J. V. Thomas; B. M. Kurup

    2004-01-01

    Bush park fishing \\/ padal fishing is an indigenous fishing method widely employed in the Ashtamudi estuary of Kerala (south India). An artificial reef made from twigs and leaves of trees is planted in the shallow areas of the estuary. The aim is to harvest fish that find shelter in these structures for the purpose of feeding and breeding. Though

  9. Mercury Dynamics in a San Francisco Estuary Tidal Wetland: Assessing Dynamics Using In Situ Measurements

    E-print Network

    Boss, Emmanuel S.

    Mercury Dynamics in a San Francisco Estuary Tidal Wetland: Assessing Dynamics Using In Situ the tidally driven exchange of mercury (Hg) between the waters of the San Francisco estuary and Browns Island, respectively--together predicted 94 % of the observed variability in measured total mercury concentra- tion

  10. SEASONAL ABUNDANCE AND DISTRIBUTION OF BIRDS ON THE SWARTKOPS ESTUARY, PORT ELIZABETH

    Microsoft Academic Search

    A. P. Martin; D. Baird

    1987-01-01

    Martin, A. P. & Baird, D. 1987. Seasonal abundance and distribution of birds on the Swartkops estuary, Port Elizabeth. Ostrich 58:122-134. Counts of estuarine birds were made on the Swartkops estuary, Port Elizabeth, between September 1983 and August 1985. Seasonal variations in the numbers of both migrant and resident species were investigated; in the austral summer, over 4000 birds were

  11. Water pollution in estuaries and coastal zones. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    NONE

    1996-02-01

    The bibliography contains citations concerning the studies of water pollution in estuaries and coastal zones. Citations examine the development, management, and protection of estuary and coastal resources. Topics include pollution sources, environmental monitoring, water chemistry, eutrophication, models, land use, government policy, and laws and regulations. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  12. www.cerf-jcr.org Benthic Nitrogen Fixation in an Eutrophic Estuary Affected

    E-print Network

    www.cerf-jcr.org Benthic Nitrogen Fixation in an Eutrophic Estuary Affected by Groundwater.A., 2012. Benthic nitrogen fixation in an eutrophic estuary affected by groundwater discharge. Journal- derived nutrient loading is known to initiate coastal eutrophication, hypoxia, and harmful algal blooms

  13. Second international symposium on the biogeochemistry of model estuaries: Estuarine processes in global change

    SciTech Connect

    Not Available

    1991-12-31

    This report consists of abstracts of papers presented at the symposium of Biogeochemistry. The main topics discussed at the meeting are; nutrient and mineral cycling, trace element distribution, sources and sinks of estuaries, sedimentation, importance of organic matter, and other biogeochemical processes of estuaries.

  14. Freshwater and marine coupling in estuaries of the Mississippi River deltaic plain

    Microsoft Academic Search

    CHRISTOPHER J. MADDEN; JOHN W. DAY; JOHN M. RANDALL

    1988-01-01

    The estuaries of Louisiana's Mississippi River deltaic plain (MRDP) exhibit sharp physical and biological contrasts due to their different successional stages in delta development. The Atchafalaya- Fourleague Bay complex is a young deltaic system with high freshwater and sediment inputs. The area has been undergoing rapid land building since 1973. The Barataria Basin estuary occupies a deltaic land mass which

  15. A CLASSIFICATION OF U.S. ESTUARIES BASED ON PHYSICAL, HYDROLOGIC ATTRIBUTES

    EPA Science Inventory

    A classification of U.S. estuaries is presented based on estuarine characteristics that have been identified as important for quantifying stressor-response relationships in coastal systems. Estuaries within a class have similar physical/hydrologic and land use characteris...

  16. Effects of tides on mixing and suspended sediment transport in macrotidal estuaries

    Microsoft Academic Search

    G. P. Allen; J. C. Salomon; P. Bassoullet; Y. Du Penhoat; C. de Grandpré

    1980-01-01

    Studies in estuaries on the French Atlantic coast, with tides ranging from 4 to 7 m, have shown that in macrotidal estuaries, semidiurnal and fortnightly tidal cycles play a significant role in controlling hydrological and sedimentological processes. During the fortnightly neap-spring cycle of tidal amplitudes, the tidal prism varies considerably, bringing about significant changes in the ratio of river flow

  17. Effect of wind events on phytoplankton blooms in the Pearl River estuary during summer

    Microsoft Academic Search

    Kedong Yin; Jianlin Zhang; Pei-Yuan Qian; Weijun Jian; Liangmin Huang; Jianfang Chen; Madeline C. S. Wu

    2004-01-01

    The Pearl River estuary fuels phytoplankton productivity in the estuarine coastal waters in the oligotrophic South China Sea. Cruises were conducted to investigate the spatial distribution of primary productivity, and two size fractionations (5?m) of chlorophyll in the Pearl River estuary and across the coastal plume south of Hong Kong during the season of high river discharge (July, 1999 and

  18. River discharge, sediment transport and exchange in the Tana Estuary, Kenya

    Microsoft Academic Search

    J. U. Kitheka; M. Obiero; P. Nthenge

    2005-01-01

    This study focuses on sediment transport and exchange dynamics in the 27km2 Tana Estuary located at Kipini in the north Kenya coast. The estuary is drained by the Tana River, which contributes more than 50% of the total river discharges into the Kenyan sector of the Indian Ocean. The study involved measurement of river discharges, estuarine flood–ebb tidal discharges, total

  19. WestuRe: U.S. Pacific Coast estuary/watershed data and R tools

    EPA Science Inventory

    There are about 350 estuaries along the U.S. Pacific Coast. Basic descriptive data for these estuaries, such as their size and watershed area, are important for coastal-scale research and conservation planning. However, this information is spread among many sources and can be dif...

  20. An Idealized Model and Systematic Process Study of Oxygen Depletion in Highly Turbid Estuaries

    E-print Network

    Talke, Stefan

    An Idealized Model and Systematic Process Study of Oxygen Depletion in Highly Turbid Estuaries S. A The sensitivity of oxygen depletion in turbid estuaries to parameters like freshwater discharge, depth of DO with SSC and temperature. Modeled DO closely tracks changes to the estuarine turbidity zone (ETZ

  1. A simple theoretical model for the flow of an estuary onto a continental shelf

    Microsoft Academic Search

    Robert C. Beardsley; John Hart

    1978-01-01

    A simple theoretical model is developed to describe the steady flow of an estuary onto an adjacent continental shelf. A two-layer density stratification is assumed for the shelf water, and the fluid motion is driven by the positive (upper layer) and negative (lower layer) mass fluxes associated with a pair of point sources located at the mouth of the estuary.

  2. Report on benthic survey/sampling at Coquille Estuary, OR: June 30-July 3, 2008

    EPA Science Inventory

    Zostera japonica is a non-native seagrass first reported in the PNW in Willapa Bay in 1957 (Harrison and Bigley 1982). Since the, Z. japonica has been reported from 16 estuaries in the PNW (Lee and Reusser 2007), including the Yaquina Estuary in 1974-1975 (Bayer 1996). Besides ...

  3. Natural and anthropogenic hydrocarbon inputs to sediments of Patos Lagoon Estuary, Brazil

    Microsoft Academic Search

    M arcia Caruso; Bõ ´ cegoc

    The Patos Lagoon Estuary, southern Brazil, is an area of environmental interest not only because of tourism, but also because of the presence of the second major port of Brazil, with the related industrial and shipping activities. Thus, potential hydrocarbon pollution was examined in this study. Sediment samples were collected at 10 sites in the estuary, extracted, and analyzed by

  4. Early Contamination by Heavy Metals of the Guadalquivir Estuary After the Aznalcóllar Mining Spill (SW Spain)

    Microsoft Academic Search

    A Gómez-Parra; J. M Forja; T. A DelValls; I Sáenz; I Riba

    2000-01-01

    The Guadalquivir estuary was impacted by the accidental release of 5 million cubic meters of acid waste from the processing of pyrite ore (25 April 1998). The waste entered ecologically sensitive and protected areas such as the National Park of Doñana. Here are presented the results obtained from a time sequence of different sampling sites in the estuary and in

  5. MODELING FISH AND SHELLFISH DISTRIBUTIONS IN THE MOBILE BAY ESTUARY, USA

    EPA Science Inventory

    Estuaries in the Gulf of Mexico provide rich habitat for many fish and shellfish, including those that have been identified as economically and ecologically important. For the Mobile Bay estuary, we developed statistical models to relate distributions of individual species and sp...

  6. Demonstration and Hands-on Exercises with the Estuary Data Mapper

    EPA Science Inventory

    The U.S. Environmental Protection Agency (US EPA) is developing e-Estuary, a decision-support system for applications of the Clean Water Act in coastal management. E-Estuary has three elements: an estuarine geo-referenced relational database, watershed GIS coverages, and tools t...

  7. ABUNDANCE AND DISTRIBUTION OF YOUNG ATLANTIC MENHADEN, Brevoortia tyrannus, IN THE WHITE OAK RIVER ESTUARY,

    E-print Network

    ABUNDANCE AND DISTRIBUTION OF YOUNG ATLANTIC MENHADEN, Brevoortia tyrannus, IN THE WHITE OAK RIVER menhaden in an estuary was investigated. Most menhaden larvae entered the estuary in March after the water the distribution of menhaden, but illumination affected catchability, since more menhaden were collected during

  8. Engineering Engineering Education

    E-print Network

    Simaan, Nabil

    E School of Engineering Engineering Education in a University Setting 292 Degree Programs in Engineering 294 Special Programs 296 Honors 298 Academic Regulations 300 Courses of Study 305 Engineering of Engineering is the largest and oldest private engineering school in the South. Classes offering engineering

  9. ^ 3 Feasibility Prototyping 3.3 A Matlab-Based Dynamic TEM Simulator

    E-print Network

    Van den Hof, Paul

    of the functionalities of cuirent TEM components and their relations from the point of view of a control engineer. Figure mccliaiiks L-iinlrollcr Fig. 3.12 Functionalities of current T E M components from a control engineering^° 3 Feasibility Prototyping 3.3 A Matlab-Based Dynamic TEM Simulator Arturo Tejada, Arjan J . den

  10. ECE 481 Ethics in Electrical and Computer Engineering Dept. of Electrical and Computer Engineering

    E-print Network

    ECE 481 Ethics in Electrical and Computer Engineering Dept. of Electrical and Computer Engineering to work with it to find a market, conduct a design feasibility study, and a preliminary design on rainwater is not feasible (it should be viewed as something one is lucky to get any of). · Women typically

  11. FEASIBILITY STUDY OF PRESSURE PULSING PIPELINE UNPLUGGING TECHNOLOGIES FOR HANFORD

    SciTech Connect

    Servin, M. A. [Washington River Protection Solutions, LLC, Richland, WA (United States); Garfield, J. S. [AEM Consulting, LLC (United States); Golcar, G. R. [AEM Consulting, LLC (United States)

    2012-12-20

    The ability to unplug key waste transfer routes is generally essential for successful tank farms operations. All transfer lines run the risk of plugging but the cross site transfer line poses increased risk due to its longer length. The loss of a transfer route needed to support the waste feed delivery mission impacts the cost and schedule of the Hanford clean up mission. This report addresses the engineering feasibility for two pressure pulse technologies, which are similar in concept, for pipeline unplugging.

  12. The Role of Feasibility Analysis in Successful Cogeneration

    E-print Network

    Wulfinghoff, D. R.

    THE ROLE OF FEASIBILITY ANALYSIS IN SUCCESSFUL COGENERATION Donald R. Wulfinghoff, P.E. Wulfinghoff Energy Services, Inc. Wheaton, ABSTRACT Although the energy crisis 'has given new impetus to cogeneration, many of the considerations... of the increasing availability of purchased electricity and the obsolescence of reciprocating steam engines. A resurrection of cogeneration occurred during the 1960's, but not within the industrial sector, and not because of the energy crisis, which had...

  13. Feasibility study on tri-hybrid desalination system

    Microsoft Academic Search

    Hyung Ho Jung; Woo Hyung Lee; Joon Ha Kim

    2010-01-01

    In the present study, the feasibility of a tri-hybrid desalination system for the production of electricity, energy for heating and cooling and water was studied. The tri-hybrid desalination system is a combination of a cogeneration and a desalination system. The system is composed of a generator driven by a gas engine, a gas boiler, a turbo-refrigerator, an absorption refrigerator for

  14. What does impacted look like? High diversity and abundance of epibiota in modified estuaries.

    PubMed

    Clark, Graeme F; Kelaher, Brendan P; Dafforn, Katherine A; Coleman, Melinda A; Knott, Nathan A; Marzinelli, Ezequiel M; Johnston, Emma L

    2015-01-01

    Ecosystems modified by human activities are generally predicted to be biologically impoverished. However, much pollution impact theory stems from laboratory or small-scale field studies, and few studies replicate at the level of estuary. Furthermore, assessments are often based on sediment contamination and infauna, and impacts to epibiota (sessile invertebrates and algae) are seldom considered. We surveyed epibiota in six estuaries in south-east Australia. Half the estuaries were relatively pristine, and half were subject to internationally high levels of contamination, urbanisation, and industrialisation. Contrary to predictions, epibiota in modified estuaries had greater coverage and were similarly diverse as those in unmodified estuaries. Change in epibiota community structure was linearly correlated with sediment-bound copper, and the tubeworm Hydroides elegans showed a strong positive correlation with sediment metals. Stressors such as metal contamination can reduce biodiversity and productivity, but others such as nutrient enrichment and resource provision may obscure signals of impact. PMID:25282127

  15. Detecting benthic community responses to pollution in estuaries: a field mesocosm approach.

    PubMed

    O'Brien, Allyson L; Keough, Michael J

    2013-04-01

    Biological stress responses in individuals are used as indicators of pollution in aquatic ecosystems, but detecting ecologically relevant responses in whole communities remains a challenge. We developed an experimental approach to detect the effects of pollution on estuarine communities using field-based mesocosms. Mesocosms containing defaunated sediments from four estuaries in southeastern Australia that varied in sediment contamination were transplanted and buried in sediments of the same four estuaries for six weeks. Mesocosm sediment properties and metal concentrations remained representative of their source locations. In each estuary, fauna communities associated with sediments derived from the site with the highest metal concentrations were significantly different from other communities. This pattern was evident for some of the individual taxa, in particular the polychaete Capitella sp. Consistent responses across estuaries suggest numbers of individuals, and especially Capitella sp., could be used to identify contaminated sediments in estuaries with similar fauna and site characteristics. PMID:23333486

  16. SALT WATER INTRUSION AND ITS RELATIONSHIP WITH ESTUARINE ECOLOGY IN THE CHIKUGOGAWA ESTUARY

    NASA Astrophysics Data System (ADS)

    Yokoyama, Katsuhide; Ohmura, Taku; Suzuki, Tomoyuki; Takashima, Soutaro

    The spatiotemporal distribution of seawater intrusion in the Chikugogawa estuary was analyzed, and its relationship with the temporal variation of phytoplankton and engraulid fish, Coilia nasus, was discussed. The Chikugogawa estuary is vertically well mixed for most of the year, and a salt wedge is observed only when the tidal range decreases to 2 m or less. We found that the ratio of chlorophyll-a to pheophytin-a during the semilunar cycle varied according to the change in the mixing conditions in the estuary. Further, the number of sampled estuarine fish was related to the salinity and tidal range within the estuary; the fish was caught when the salinity was low and the tidal range was large. It is necessary to regulate the fresh water discharge in the estuary in order to maintain a low-salinity region that is suitable for the migration of fish and their spawning areas to the downstream of the river mouth barrage.

  17. Total mercury in sediments and in Brazilian Ariidae catfish from two estuaries under different anthropogenic influence.

    PubMed

    Azevedo, Juliana S; Braga, Elisabete S; Favaro, Deborah T; Perretti, Adriana R; Rezende, Carlos Eduardo; Souza, Cristina Maria M

    2011-12-01

    Santos-São Vicente estuary, located in São Paulo State, Brazil, has a history of contamination by inorganic chemicals such as mercury (Hg). In the 1980s the Cubatão was considered one of the most polluted sites in the world as a consequence of the intense industrial activities located in the city close to the estuary. To provide data and evaluate the local biota, total mercury (THg) contents were determined in sediments and in fish, Cathorops spixii, from different areas of the Santos-São Vicente estuary. For comparison, samples were also collected in a non-polluted system with similar hydrochemistry characteristics, the Cananeia estuary. The water characteristics and THg levels in sediment and fish samples confirmed a high human influence in the Santos-São Vicente estuary. The lowest THg values, observed in Cananeia, were evidence of low anthropogenic influence. High values observed in Santos-São Vicente show the necessity for a monitoring program. PMID:22030105

  18. STOL ride control feasibility study

    NASA Technical Reports Server (NTRS)

    Gordon, C. K.; Dodson, R. O.

    1973-01-01

    The feasibility of developing a ride-smoothing control system for a 20-passenger turboprop STOL transport was assessed. Five different ride-control system configurations with varying degrees of complexity, performance, and cost were investigated. Results indicate that a satisfactory ride-control system can be practically implemented on the aircraft with minimum flight performance degradation.

  19. Library Data Processing Feasibility Report.

    ERIC Educational Resources Information Center

    Mears, M. J.; And Others

    To establish the precise effects of using MARC II in West Sussex, and how it could assist the library staff were the goals of this feasibility study. It illustrates the development of the library catalog and associated systems as both realistic and practical. It indicates what kind of repercussions will be felt by the library and how it could…

  20. Heavy Metals (Cd, Cu, Cr, Pb and Zn) in Meretrix meretrix Roding, Water and Sediments from Estuaries in Sabah, North Borneo

    ERIC Educational Resources Information Center

    Abdullah, Mohd. Harun; Sidi, Jovita; Aris, Ahmad Zaharin

    2007-01-01

    Concentrations of heavy metals (Cd, Cu, Cr, Pb and Zn) in tissues of Meretrix meretrix Roding (M. meretrix R.), water and sediments from two estuaries were determined. One estuary is located in an urban area of Kota Kinabalu (Likas estuary) and the other in a rural district of Kota Belud (Kota Belud estuary), where both are in Sabah, North of…